Legal Question in Family Law in New York

Re: Child Custody

This is a complicated question. A blood relative can bring an action.

If, in that action, the parent is found to be inappropriate, then the blood relative can make himself available as a guardian.

A non-blood relation can report the abuse/neglect to ACS and later petition to become the guardian with a much lower probability than a blood relative.

A grandparent stands in a wholly different place. a grandparent can petition for custody directly as an interested party. this is new law and a new practice and may not be accepted initially by all courts, so a lawyer is needed to present the petition.

Overall, in the absence of abuse/neglect there is no chance of a non-parent gaining custody from a custodial parent.

This is a confused answer, but the question is a little vague. If you clarify the question with more information, I can be more specific in my answer.