In Matter of Bennett v. Jeffreys, 40 NY2d 543, 387 N.Y.S.2d 821, dealing with circumstances where a child was entrusted to another woman shortly after birth and the biological mother petitioned for custody eight years later, the Court of Appeals held that a person who was not a biological parent would have standing to apply for custody, in the face of opposition by a biological parent, upon proof of "abandonment, unfitness, persistent neglect, unfortunate or involuntary extended disruption of custody, or other equivalent but rare extraordinary circumstances which would drastically affect the welfare of the child."