Order unanimously affirmed with costs. Memorandum: Petitioner appeals from an order dismissing his petition for modification of a divorce decree to grant him custody of the infant children. The standard for modifying a prior custody award is well established: the best interests of the children under the prevailing circumstances (see, Friederwitzer v Friederwitzer, 55 N.Y.2d 89, 95; Matter of Borst v Borst, 137 A.D.2d 890, 891; Matter of Robb v McIntosh, 99 A.D.2d 571). Where modification of an existing custody decree is sought, the prior decree and the circumstances on which it was based must be given great consideration because stability is a significant factor in determining a child's best interests (Friederwitzer v Friederwitzer, supra; Matter of Nehra v Uhlar, 43 N.Y.2d 242, 250). There was no evidence adduced at the hearing that respondent was an unfit parent and, in fact, the court-appointed psychologist testified that both parents were equally capable of raising the children. Nor was there any evidence to support petitioner's allegation that respondent was suffering from a mental illness.
Family Court's determination was based on the testimony of the witnesses, psychological reports, and an in camera interview with the children. The determination dismissing the petition is a matter addressed to the discretion of the court and we decline to disturb it (see, Matter of Darlene T., 28 N.Y.2d 391, 395; Matter of Robb v McIntosh, supra).