Ordered that the order is affirmed insofar as appealed from, with costs. "[W]here parents enter into an agreement concerning custody it will not be set aside unless there is a sufficient change in circumstances since the time of the stipulation and unless the modification of the custody agreement is in the best interests of the [children]" ( McNally v McNally, 28 AD3d 526, 527 [internal quotation marks omitted]; see Peterson v Peterson, 73 AD3d 1005; Matter of Lopez v Infante, 55 AD3d 837, 837-838). "Moreover, [a] noncustodial parent seeking a change in custody is not automatically entitled to a hearing, but must make an evidentiary showing sufficient to warrant a hearing" ( Peterson v Peterson, 73 AD3d at 1006 [internal quotation marks omitted]; see Jean v Jean, 59 AD3d 599, 600; Matter of Lopez v Infante, 55 AD3d at 838; Matter of Bauman v Abbate, 48 AD3d 679, 680; Spratt v Fontana, 46 AD3d 670, 671; Green v Green, 43 AD3d 867; DiVittorio v DiVittorio, 36 AD3d 848, 849; McNally v McNally, 28 AD3d at 527).
Contrary to the mother's contention, the Family Court properly dismissed, without a hearing, her petition to modify a prior order so as to award her sole custody. Where possible, custody should be established on a long term basis, "at least so long as the custodial parent has not been shown to be unfit, or perhaps less fit, to continue as the proper custodian" ( Obey v Degling, 37 NY2d 768, 770; see Matter of Lopez v Infante, 55 AD3d 837; DiVittorio v DiVittorio, 36 AD3d 848, 849; Jackson v Jackson, 31 AD3d 386). A noncustodial parent seeking a change of custody is not entitled to a hearing without making some evidentiary showing sufficient to warrant a hearing ( see Matter of Lopez v Infante, 55 AD3d at 838; Matter of Bauman v Abbate, 48 AD3d 679, 680; DiVittorio v DiVittorio, 36 AD3d at 849). Here, the mother failed to make such a showing.
“A noncustodial parent seeking a change of custody is not entitled to a hearing without making some evidentiary showing sufficient to warrant a hearing” (Matter of Lopez v. Infante, 55 A.D.3d 837, 838, 866 N.Y.S.2d 295 ; see Matter of Olds v. Binyard, 64 A.D.3d 658, 659, 882 N.Y.S.2d 495 ; Jean v. Jean, 59 A.D.3d 599, 600, 875 N.Y.S.2d 88 ; Matter of Bauman v. Abbate, 48 A.D.3d 679, 680, 850 N.Y.S.2d 921 ).
Kells appeals, and we affirm insofar as appealed from. Contrary to Kells's contention, the Family Court was not required to hold a separate evidentiary hearing on the issue of whether there had been a sufficient change of circumstances since the entry of the joint custody order before it proceeded to a best interests hearing ( cf. Friederwitzer v Friederwitzer, 55 NY2d 89, 93-94; Stysis v Stysis, 70 AD3d 672; Salick v Salick, 66 AD3d 757; Matter of Lopez v Infante, 55 AD3d 837, 838). Although courts require some evidentiary showing warranting a modification in the best interests of the children ( see Teuschler v Teuschler, 242 AD2d 289, 290; Matter of Miller v Lee, 225 AD2d 778, 779), the Family Court providently exercised its discretion in finding that Pappas had shown that the discord between the parties had escalated to a point where they could no longer cooperate on matters concerning the children and, therefore, joint custody was no longer feasible ( see Bliss v Ach, 56 NY2d 995, 998; Braiman v Braiman, 44 NY2d 584, 587; Matter of Lovitch v Lovitch, 64 AD3d 710, 712; Matter of Francis v Cox, 57 AD3d 776, 777). In any custody dispute, the standard ultimately to be applied remains the best interests of the children when all of the applicable factors are considered ( see Eschbach v Eschbach, 56 NY2d 167, 171; Friederwitzer v Friederwitzer, 55 NY2d at 95).
Ordered that the order is affirmed, without costs or disbursements. "[W]here parents enter into an agreement concerning custody, it will not be set aside unless there is a sufficient change in circumstances since the time of the stipulation and unless the modification of the custody agreement is in the best interests of the child" ( Matter of Lopez v Infante, 55 AD3d 837, 837-838). The Family Court's determination to deny, after a hearing, the father's petition for a change of custody of the parties' children is supported by a sound and substantial basis in the record ( see Matter of Marriott v Hernandez, 55 AD3d 613, 613-614; Matter of Moorehead v Moorehead, 197 AD2d 517, 519).
"`Modification of an existing custody arrangement is permissible only upon a showing that there has been a change in circumstances such that a modification is necessary to ensure the continued best interests and welfare of the child' ( Matter of Pignataro v Davis, 8 AD3d 487, 488)" ( Matter of Watson v Smith, 52 AD3d 615, 616; see Matter of Adornato v Adornato, 63 AD3d 920; Matter of Meyers v Sheehan, 62 AD3d 802, 803; Matter of Gurewich v Gurewich, 58 AD3d 628, 629; Foley v Foley, 52 AD3d 773, 774). "A noncustodial parent seeking a change of custody is not entitled to a hearing without making some evidentiary showing sufficient to warrant a hearing" ( Matter of Lopez v Infante, 55 AD3d 837, 838 [citations omitted]; see Matter of Olds v Binyard, 64 AD3d 658, 659; Jean v Jean, 59 AD3d 599; Matter of Bauman v Abbate, 48 AD3d 679, 680; Spratt v Fontana, 46 AD3d 670, 671; Green v Green, 43 AD3d 867). The father failed to make the requisite showing to warrant a hearing. His conclusory and nonspecific allegations, unsupported by any evidentiary snowing, were insufficient to warrant a hearing ( see Matter of Blackstock v Price, 51 AD3d 914, 915; Arcabascio v Arcabascio, 48 AD3d 606, 607).
Ordered that the order is affirmed insofar as appealed from, without costs or disbursements. In determining whether to modify a custody arrangement to which the parties voluntarily agreed, the principal issue before the court is whether a change in circumstances warrants a modification in the best interests of the child ( see Matter of Awan v Awan, 63 AD3d 733, 734; Matter of Lopez v Infante, 55 AD3d 837, 838; Matter of Penn v Penn, 41 AD3d 724, 724-725). Since custody determinations depend to a great extent upon an assessment of the character and credibility of the parties and witnesses, deference is accorded to the Family Court's findings, and such findings will not be disturbed unless they lack a sound and substantial basis in the record ( see Matter of Perez v Martinez, 52 AD3d 518, 519; Matter of Langlaise v Sookhan, 48 AD3d 685; Matter of Tavarez v Musse, 31 AD3d 458).