In determining the best interests of the children in a child custody dispute, the court must evaluate the totality of the circumstances. The care and affection shown; the stability of the respective parents; the atmosphere of the homes; the ability and availability of the parents; the morality of the parents; the prospective educational probability; the possible effect of custodial change on the children; the financial standing of the parents and parents’ past performances are but a few of the areas requiring exploration. Informal custodial arrangements and even temporary custody orders, issued without the benefit of a full plenary hearing, are factors relevant to the ultimate custody determination.
Additionally, the stability of the child’s environment and a reluctance to uproot him or her from familiar surroundings are quite properly relevant and important considerations. On the other hand, the fact that a sudden change in custody may prove temporarily disruptive for the children is not determinative. For example, where all mental health experts who testified at the hearing concluded that the risk of emotional trauma caused by the change in custody was outweighed by the risk that the child would sustain emotional trauma if she remained in the mother’s custody, given the mother’s deliberate efforts to interfere with the father’s visitation rights and false allegations of sexual misconduct.
Source: Westlaw – Callagan’s Family Court and Law Practice New York