To modify an existing custody arrangement, there must be a showing of a change in circumstances such that modification is required to protect the best interests of the child (see Matter of Zeis v Slater, 57 AD3d 793, 794 [2008]). The best interests of the child are determined by a review of the totality of the circumstances (see Eschbach v Eschbach, 56 NY2d 167, 172 [1982]). Deference should be accorded the hearing court, which saw and heard the witnesses, and the hearing court’s custody *861determination should not be set aside unless it lacks a sound and substantial basis in the record (see Matter of Zeis v Slater, 57 AD3d at 794).
Here, the Family Court’s determination that the mother failed to satisfy her burden of demonstrating a change of circumstances warranting a change of custody is supported by a sound and substantial basis in the record. The mother “presented no evidence of parental alienation that would justify a change in physical custody” (Matter of Roelofsen v Tiberie, 64 AD3d 603, 604 [2009]). Accordingly, we decline to disturb the Family Court’s determination (see Matter of Roelofsen v Tiberie, 64 AD3d 603 [2009]; see also Matter of Chase v Matanda-Chase, 41 AD3d 475, 476 [2007]; Matter of Bryant v Nazario, 306 AD2d 529 [2003]).
The mother’s remaining contentions are without merit. Dillon, J.P., Florio, Miller and Angiolillo, JJ., concur.