Celinas, J.
Less than five months after the entry of a judgment of divorce nisi that incorporated an agreement of the parties providing that the defendant (mother) was to have physical custody of the parties’ two minor children, Molly and Tom,2 the plaintiff (father) filed a complaint for modification alleging [783]*783various changes in circumstances and requesting (1) that the divorce judgment be modified by transferring to him physical custody of Tom and (2) that Tom be allowed to relocate to the State of Connecticut where the father resided. The mother responded with a motion for summary judgment, which was allowed by the judge. As we agree with the father that summary judgment should not have entered for the mother, we vacate the judgment dismissing the father’s complaint for modification and remand the matter to the Probate and Family Court for further proceedings consistent with this opinion.
1. Background. The parties were married in 1984 and were divorced by a judgment of divorce nisi dated January 30, 2004. During the divorce proceedings the parties executed a separation agreement, which provided that they would share legal custody of the minor children and that the mother would have sole physical custody of the children.3 The judgment of divorce nisi appears to have incorporated that provision of the agreement.
On or about June 11, 2004, the father filed a complaint for modification alleging, as changes in circumstances, that the mother was neglecting, abusing, or otherwise ignoring Tom, that Tom had “become extremely lonely and depressed” as a result of the lack of attention, and that Tom, on numerous occasions since the divorce, had expressed his desire to live with the father.4 The father requested that the court modify the divorce judgment so as to award him physical custody, or “at least shared physical custody,” of Tom and that Tom be allowed to relocate to Connecticut. Thereafter, the judge appointed counsel for the children and, on the father’s motion, a guardian ad litem to investigate and make findings concerning the physical custody of the minor children and a visitation schedule for the children.
2. The guardian ad litem’s reports. The guardian ad litem, Linda Cavallero, Ph.D.,5 submitted a thirty-three page initial report in November, 2005, and a supplemental report in Febru[784]*784ary, 2006. Both reports are included in their entirety in the summary judgment materials and are relied on by the parties. Doctor Cavallero interviewed both the parties and the children on multiple occasions. In addition, she spoke with numerous “collateral contacts,” including Helena Friedman, the children’s (former) attorney; Peter G. Grey, Ph.D, a psychological consultant retained by the parties to help them “work out” an agreement on child issues; the children’s former and present nannies; the children’s pediatrician; and a number of educators at the children’s schools. Doctor Cavallero also conducted psychological testing on the parties and reviewed dozens of “records,” including a letter of Dr. Grey to the parties dated October 21, 2004 (discussed infra).
Doctor Cavallero indicated that the parties are well educated successful professionals. Their divorce was a bitter one. The father reported to Dr. Cavallero that since the divorce Tom has repeatedly requested to live with him. The father also voiced his concern that the mother paid little attention to Tom and that Tom was “lonely” at her home. Tom reported to Dr. Cavallero that his mother leaves for work in the morning before he leaves for school; the nanny drops him off at the bus stop and picks him up later. Continuing, Tom stated that although he sometimes “do[es] things” with his mother in the evening, they really do not “do much.” Tom acknowledged that, on occasion, he goes for a bicycle ride or plays golf with his mother. Tom indicated that he would like to try living with his father and “thinks” that his mother told him it would be all right with her. Tom stated that the “bad side” of such an arrangement would be that he would not see his mother as much. Tom reported that he was not really close to his sister. School personnel reported to Dr. Cavallero that Tom was doing well in school and was a “pleasure” to have in class. The children’s current nanny, a college student and friend of Molly, “expressed no concern about the children.”
Helena Friedman, who was involved with the family as counsel for the children between August, 2004, and the spring of 2005, reported that Tom had told her that he does a lot of activities with his father and that with his mother he goes to the movies, shops, plays golf, and has friends over. Tom informed Friedman that he wanted to live with his father and included within [785]*785his reasons that the “mother spent a lot of time going with [Molly] to the barn for horseback riding [counsel stated that Molly was involved with horseback riding on a daily basis; she apparently owns or has regular access to a horse], and that he had more fun at his father’s house.”
Doctor Peter Grey, who met with the parties and the children (on two occasions) to better understand the family situation, reported to the guardian ad litem that both parents are “very busy and stated that the children were raised by whoever was with them.” He described Molly as “indulged” and “something of a ‘manipulator’ ” and stated that the mother’s household “seemed to be setup around [Molly’s] needs more than [Tom’s].” He noted, for example, that when Molly went for riding lessons, Tom had to go along and spent his afternoon in the car rather than playing with peers. Doctor Grey reported that Tom “was not ‘the prize child’ at least by the mother.”
A nanny who had cared for the children for seven years (until the summer of 2002), but who had subsequently been given some access to the children by the father, expressed concern that Tom “does not seem happy and that other people who have known him for a long time report that he looks ‘sad.’ ”
Doctor Cavallero stated in her conclusions in her initial report that, in her opinion, “both parents are basically capable and love their children. [The mother’s] strengths as a parent are her hard work and her commitment to her children.” She noted, however, that the father appears to have a better appreciation of Tom’s needs and experience, and that his “strengths are his empathy for both children, especially [Tom], and his willingness to adapt his current schedule to meet their needs.” In contrast, the mother “tends to view the situation from her perspective” and in a “self-serving manner.” Doctor Cavallero stated that the father “correctly notes that [Tom] is somewhat lonely in the mother’s household, that his needs are not the priority and that [Tom] frequently comes second to the needs of his sister and his mother” (emphasis supplied). Doctor Cavallero also stated that Tom had consistently expressed his preference to live with his father to numerous individuals (including Dr. Grey, attorney Friedman, his parents, and the guardian ad litem) and had stated as reasons that he had a longing to spend more time with his father, that he had [786]*786been unable to spend consecutive days with him, and that he enjoyed the activities that he engaged in with his father. Doctor Cavallero opined and recommended that “given [Tom’s] long standing and developmentally appropriate request to live with his father and his apparently well-reasoned rationale, [Tom] should be allowed to move to the primary custody of his father with an access schedule with his mother comparable to what he has at the present with his father.”
Pursuant to an order of the court directing the guardian ad litem to speak with the child’s current therapist, Dr. Cavallero contacted Anthony Wolf, Ph.D, who had been seeing Tom since some time after November 10, 2004, and submitted a supplemental report. Doctor Wolf reported on February 18, 2006, that at the time therapy began, Tom was suffering from stomach aches that most likely were related to stress. Indeed, both parents had expressed their concern that Tom was in the middle of their contentious disagreements concerning the divorce and parenting plan. Continuing, Dr. Wolf reported that Tom’s stomach aches had substantially diminished and that he appears to be a well-functioning child who has a good relationship with his mother and enjoys the time he spends with his father. He described Tom as “generally upbeat” and did not think that he was depressed. Doctor Wolf acknowledged that he generally hears about “issues” from the mother, not from Tom, but stated that Tom is “pretty open” if questions are asked. Doctor Wolf also stated that at an earlier point in time when he discussed with Tom the possibility of living with his father, Tom had expressed an interest in spending more time with his father, although Dr. Wolf was not sure that Tom had thought through the issues thoroughly. Doctor Cavallero declined to modify her conclusions or recommendations as stated in her principal report subsequent to her conversation with Dr. Wolf.
3. The motion for summary judgment and opposition thereto. On May 31, 2006, the mother filed a motion for summary judgment and an affidavit of undisputed facts (supported by numerous papers, including excerpts from the guardian ad litem’s report, the guardian ad litem’s supplemental report, excerpts from deposition transcripts, and school records). See Mass.R.Dom.Rel.P. 56(a) (1997). The mother averred in her affidavit that she did [787]*787“not believe that anything [had] changed since the date of the divorce . . . that would warrant a change in custody.” She stated, among other things, that Tom was a well behaved and well adjusted child with whom she participated in many activities, including golf and bicycle riding. She also stated that Tom participates in various sports, including karate, baseball, and swimming (activities which, she states, she attends), that he is in a stable environment,6 and that he is doing well in school. Pointing to Dr. Cavallero’s reports, the mother stated that at no time did the guardian ad litem find (nor did Dr. Grey, Dr. Wolf, or attorney Friedman report) that she had neglected or abused Tom or that Tom was depressed. To the contrary, the mother stated that Dr. Cavallero had found that she (the mother) was capable and loved her children, and that Dr. Wolf had concluded that Tom was not depressed and was generally upbeat. The mother also stated that the father had moved on several occasions within Connecticut, that a subsequent marriage of the father had been annulled, and that she did not believe that the father could provide a stable home for Tom. The mother indicated that Tom had never been away from home for more than two weeks and that a dramatic change in his living conditions (e.g., a new home, a new school, and new classmates) could be detrimental to him.
Thereafter, pursuant to Mass.R.Dom.Rel.P. 56(b) (2000), the father filed an opposition to the mother’s motion together with an affidavit of disputed facts (supported by numerous papers) (rule 56[b] affidavit) and an affidavit of undisputed facts. A central thrust of the father’s rule 56(b) affidavit is that the mother had misrepresented Dr. Cavallero’s report and that the guardian ad litem did, in fact, find that Tom was lonely and neglected in the mother’s household and that his needs were not being met by the mother. The father also attached as an exhibit to his rule 56(b) affidavit a letter from Dr. Grey to the parties dated October 21, 2004.7 Doctor Grey states in his letter that Molly (who, Dr. Grey noted, has an active social life) was heavily invested in her equestrian interests and, in a very adolescent way, “is aware that [788]*788[Tom] exists but doesn’t pay much attention to him.” Continuing, Dr. Grey stated:
“Ten-year-old [Tom] presents a more complex picture and I have explained to both of you that I am concerned about his being more than just unhappy. He is dismayed about your arguing and suggests that the attention paid to [Molly] shortchanges him. Most importantly he is tom by the notion that his feelings about where he might like to live would wound or hurt one of you. Regardless of the decision (for which the adults in this matter need to be responsible) I believe that all of the parties need to work together so that he is not emotionally harmed. In my opinion, [Tom] is a child at risk to become clinically depressed.”
The father also averred that Tom had missed all or part of forty-three days of school in the last one and one-half years and that he was no longer involved in many sporting activities (which, he stated, the mother seldom attended). In addition, the father stated that because he had made new hires in his business, he had a “great deal more flexibility” to be with Tom. The father stated in his mle 56(b) affidavit that Tom is not given attention by his mother, that his needs are not being met, and that he continues to be a “second class citizen to his sister who” is indulged by the mother. Continuing, the father stated that Tom has requested repeatedly that the father “continue [the modification] process because he does not want to live in his mother’s household.”
4. The memorandum of decision and judgment. After a hearing on the motion, the judge issued a memorandum of decision in which he found that “while there are many allegations, assertions and charges made, there is an absence of genuine issues of material fact in dispute.”8 The judge noted, for example, that “some of the assertions predate the entry of the divorce” and “[t]hat a [789]*789ten year old boy may have ‘reflected’ that he wants to live with another parent is not necessarily surprising or unusual but does not rise to the level of the required change of circumstances even if proven.” Continuing, the judge stated that “[i]n terms of genuine issues of material fact to be tried regarding the allegations of [the mother’s] ignoring, neglecting and abusing the child, they do not exist.” The judge stated that the father’s “offers of proof simply cannot show that [the mother] is neglecting [Tom], even when considered in a light most favorable to [the father]. In place of evidence from which a trier of fact can infer that [Tom] is neglected, [the father] has produced conclusory statements and allegations by him not grounded on [the father’s] personal knowledge.” Based on the foregoing, the judge determined that the mother was entitled to summary judgment and dismissed the father’s complaint for modification.9
5. The governing legal principles. Rule 56(a) of the Rules of Domestic Relations Procedure provides that “[a] party may move for summary judgment subsequent to the commencement of any proceeding under these rules in actions for modification and actions to modify or enforce a foreign judgment.” A judge shall grant a motion for summary judgment “if the pleadings, depositions, answers to interrogatories, and responses to requests for admission under [Mass.R.Dom.Rel.P.] 36, together with the affidavits, if any, show that there is no genuine issue as to any material fact and that the moving party is entitled to a judgment as a matter of law.” Mass.R.Dom.Rel.P. 56(h) (2003). The moving party, here the mother, “must ‘affirmatively demonstrate] that there is no genuine issue of material fact on every relevant issue, even if [she] would have no burden on an issue if the case were to go to trial.’ ” Department of Rev. v. Mason M., 439 Mass. 665, 674 (2003), quoting from Pederson v. Time, Inc., 404 Mass. 14, 17 (1989). See Kernan v. Morse, 69 Mass. App. Ct. 378, 382 (2007). See also Jupin v. Kask, 447 Mass. 141, 146 (2006) (party moving for summary judgment “may prevail by showing that the nonmoving party has no reasonable expectation of proving an essential element of his case at trial”). All eviden[790]*790tiary inferences are to be resolved in favor of the party opposing the motion for summary judgment. Nunez v. Carrabba’s Italian Grill, Inc., 448 Mass. 170, 174 (2007). “In deciding a motion for summary judgment, a court does not resolve issues of material fact, assess credibility, or weigh evidence.” Kernan v. Morse, 69 Mass. App. Ct. at 382.
While an original judgment awarding sole physical custody of a child to a party is presumed to have been right, Hersey v. Hersey, 271 Mass. 545, 554 (1930); Rosenthal v. Money, 51 Mass. App. Ct. 257, 261 (2001), it is not immune from modification. General Laws c. 208, § 28, provides that a judge of the Probate and Family Court may modify an earlier divorce judgment concerning the custody of a minor child on finding “that a material and substantial change in the circumstances of the parties has occurred and the judgment of modification is necessary in the best interests of the children.” See Ardizoni v. Raymond, 40 Mass. App. Ct. 734, 738 (1996) (in determining modifications of custody awards based on changed circumstances, “the guiding principle always has been the best interests of the children”). An award of custody will not be sustained “unless all relevant factors in determining the best interests of the child have been weighed.” Rosenberg v. Merida, 428 Mass. 182, 191 (1998), quoting from Bouchard v. Bouchard, 12 Mass. App. Ct. 899, 899 (1981).10 As the present case appears to raise for the first time before an appellate court of the Commonwealth the propriety of a grant of summary judgment in the child custody context,11 we comment initially on the use of summary judgment in custody modification proceedings.
We perceive nothing in the language of Mass.R.Dom.Rel.P. 56,12 or in the nature of child custody in general, cf. Houston v. [791]*791Houston, 64 Mass. App. Ct. 529, 534-535 (2005) (child custody “holds a peculiar place in our jurisprudence and implicates a ‘societal interest’ ”), that would necessarily preclude the use of summary judgment in child custody modification actions.13 The parties in the present case do not contend otherwise. That said, we think it is important that a judge proceed with great caution in deciding whether summary judgment is appropriate in a custody modification proceeding. Both the question whether there has been a material change in circumstances, and, if so, the question whether modification is necessary in the best interests of the children, will most often involve the resolution of disputed issues of material fact or the weighing of evidence. Such considerations, as we have stated, would render inappropriate summary judgment. With regard to the former question, we recognize that in the initial instance the judge must review the factual allegations to determine whether they involve facts that are material, see Attorney Gen. v. Bailey, 386 Mass. 367, 370, cert, denied, 459 U.S. 970 (1982), quoting from H & M Cake Box, Inc. v. Bakery & Confectionery Workers, Intl. Union, Local 45, 454 F.2d 716, 719 (1st Cir. 1972) (“court should only ‘determine whether a genuine issue of material fact exist[s]’ ”); disputed facts are material only if they have a bearing on the outcome of the case. Jupin v. Kask, 447 Mass, at 145-146. Once the judge determines that there are facts bearing on the outcome of a custodial contest that are in dispute, summary judgment does not he. See Brush v. Brush, 414 So. 2d 37, 38 (Fla. App. 1982) (“We caution that summary judg[792]*792merits should be granted sparingly upon petitions for modification of custody because of the inherent factual disputes prevalent in such proceedings”).
Furthermore, in most cases, once a determination is made that there has been a material change in circumstances, summary judgment will be inappropriate. This is especially so in light of the “widest range of permissible evidence” that the judge may consider in determining a child’s best interests. Ardizoni v. Raymond, 40 Mass. App. Ct. at 738. See Adoption of Irene, 54 Mass. App. Ct. 613, 617 (2002) (“[w]here the objective is a . . . child’s best interests, factual determinations are necessarily involved”).14 Cf. Goulart v. Canton Hous. Authy., 57 Mass. App. Ct. 440, 441 (2003) (“Ordinarily, summary judgment is not an appropriate means to resolve negligence cases, because usually the question of negligence is one of fact”). Each case must be carefully analyzed and any “[djoubts as to the existence of a genuine issue of material fact are to be resolved against the party moving for summary judgment.” Allmerica Fin. Corp. v. Certain Underwriters at Lloyd’s, London, 449 Mass. 621, 628 (2007).
6. Factual issues. The father argues that the judge erred in determining that no genuine issues of material fact exist regarding his allegations that the mother neglected Tom and further erred in determining that the evidence, viewed in the light most favorable to him, cannot show that the mother was neglecting Tom. We agree with the father that summary judgment should not have entered for the mother.
At the outset, we note that the mother, in arguing that the father cannot demonstrate, and there is no evidence, that she has been neglecting Tom since the January, 2004, judgment, takes the position that “neglect” must be interpreted in accordance with the regulations of the Department of Children and Families to mean the “failure by a caretaker, either deliberately or through negligence or inability, to take those actions necessary to provide a child with minimally adequate food, clothing, shelter, medical care, supervision, emotional stability and growth, [793]*793or other essential care ...” (emphasis in original). 110 Code Mass. Regs. § 2.00 (1996). In the mother’s view, her conduct must “rise to this high level” to be sufficient to warrant the drastic measure of a change of custody. Putting to one side the facts that the mother cites to no authority in support of her position and that her memorandum in support of her motion for summary judgment makes no reference to the above quoted definition (which was in effect at the time her motion was heard),15 we reject such a restrictive view of “neglect” in custody modification actions. As stated in the American Law Institute’s (ALI) Principles of the Law of Family Dissolution, the changed-circumstances test “does [not] require circumstances as severe as those that require the state to intervene under its abuse and neglect statutes. There are circumstances that might justify a parent in obtaining an alteration in his or her child’s custodial arrangement that would not otherwise justify interference by the state.” ALI, Principles of the Law of Family Dissolution: Analysis and Recommendations § 2.15 comment c (2002).16
Viewing the evidence in the light most favorable to the father, it reasonably can be inferred from Dr. Cavallero’s reports and Dr. Grey’s letter of October 21, 2004, that although the mother has engaged in some activities with Tom and has ensured that he is seeing a therapist, Tom’s emotional needs are not being adequately met in the mother’s household as he is largely ignored there. Such evidence includes (1) Tom’s report to Dr. Cavallero that he does not “do much” with his mother, his suggestion to Dr. Grey that the attention paid to Molly “shortchanges him,” and his repeated requests (discussed more fully, infra) that he be allowed to live with his father; (2) Dr. Grey’s observations that the mother’s household seems to be set up around Molly’s needs more than Tom’s and that the mother is invested primarily in [794]*794activities with Molly that draw Tom from his peers; and (3) Dr. Cavallero’s statements that Tom’s needs are not the priority and “frequently come second to the needs of [Molly] and [the mother].”17 Moreover, Dr. Cavallero stated specifically that Tom is somewhat lonely in the mother’s household and Dr. Grey voiced his concern about the child being “more than just unhappy” and “at risk to becoming clinically depressed.”18 Such evidence is, of course, contrary to the mother’s statements and evidence that the [795]*795child is doing well in her household, that his needs are being met, and that he is not neglected.
Further evidence bearing on the issue of “neglect” and its impact on the child’s emotional health may be found in the child’s repeated and, apparently, more urgent requests that he be allowed to live with the father. While a child’s expression of custodial preference must be treated with caution and the preference of an eleven year old child is not given decisive weight,19 it is a factor to be considered by the court in the context of all other circumstances. See Custody of Vaughn, 422 Mass. 590, 599 n.11 (1996); Hale v. Hale, 12 Mass. App. Ct. 812, 820 (1981); Ardizoni v. Raymond, 40 Mass. App. Ct. at 738-739; Abbott v. Virusso, 68 Mass. App. Ct. 326, 337-338 (2007), S.C., 450 Mass. 1031 (2008). See also ALI, Principles of the Law of Family Dissolution: Analysis and Recommendations § 2.16 comment e (“In a majority of jurisdictions that require a showing of changed circumstances before a custody order may be modified, a child’s wish for a custody change ordinarily will not, in itself, constitute a sufficient change of circumstances!;] . . . [i]n combination with other factors, however, a child’s preference often appears to make a difference”); 2 Atkinson, Modem Child Custody Practice § 10.1 (2007) (while holdings of some courts that child’s preference to live with noncustodial parent is not, by itself, sufficient basis to modify custody, “the practical meaning of the holding is that a child’s preference is often not enough to modify custody if the child gives no reason for the preference or if the reason given is not a good one”).
The mother also argues that the father did not sustain his “burden to show that the ‘changed circumstances’ did not exist prior to the most recent judgment.” More specifically, she states that the father cannot “show, and there is no evidence on the record to demonstrate, that [she] behaved any differently toward [Tom] before the January 30, 2004, judgment than she did [796]*796afterwards.”20 The mother also notes, correctly, that Tom expressed a preference to reside with the father before the divorce (although she acknowledges that “according to the father, the frequency of, and the manner in which such statements were made increased thereafter”).
As a threshold matter, the summary judgment materials are sketchy as to the mother’s possible inattention toward Tom prior to the divorce and the then effect (if any) of such conduct upon the child. At all events, there was evidence in the present case in (at least) the form of Tom’s complaints subsequent to the divorce concerning the mother’s conduct toward him; Tom’s increasing insistence that he be allowed to live with his father, see Basden v. Cole, 123 P.3d 566, 569-570 (Wyo. 2005) (although child had expressed preference to live with mother prior to divorce, in determining whether there has been change in circumstances in custody modification action judge properly may consider with other factors child’s more urgent expressions of preference to live with mother subsequent to divorce); the statements of Dr. Cavallero and Dr. Grey that Tom’s needs are not a priority in the mother’s household; and Dr. Grey’s concerns about Tom being “more than just unhappy” and “at risk to becoming clinically depressed” (see note 18, supra) which, when viewed in the light most favorable to the father, could support a finding of a material change in circumstances.21 Cf. Freedman v. Freedman, 49 Mass. App. Ct. 519, 522-523 (2000) (if alternating custody arrangement is not operating in best interests of child, Probate and Family Court has power to reexamine arrangement “as an adverse effect on the child would constitute a material change in circumstances”); Hernandez v. Branciforte, 55 Mass. App. Ct. 212, [797]*797220 (2002) (upholding transfer in custody where probate judge, in determining whether there had been material change in circumstances, concluded, inter alia, that mother’s performance as custodial parent demonstrated that she was not able to separate her needs and interests from those of child). But compare Fuller v. Fuller, 2 Mass. App. Ct. 372, 377 (1974) (where there was no evidence that custodial parent had, in any respect, been inadequate parent); Delmolino v. Nance, 14 Mass. App. Ct. 209, 213-214 (1982).
7. Conclusion. The judgment dismissing the husband’s complaint for modification is vacated and the matter is remanded to the Probate and Family Court for further proceedings. The mother’s request for appellate attorney’s fees is denied.
So ordered.