child custody

o.k. i'll try to make this as clear as possible. my fiance had a child with his ex-girlfriend 4/99. they llived together for a few months after the baby was born. she did not put his name on the birth certificate, but has told him it was his from the moment she found out that she was pregnant. 4/11/00 she was sentenced to 17 months in prison for a felony probation violation. she gave the baby to her sister and him taken to ky to her other sisters house so that we could not see him. there is no custody order and never has been. she was supposed to have dna tests done several times, but never keeps the appiontments. We took the baby from her before in nov. and had him for about 6 weeks. we started letting her keep him for a few days and then we would keep him. we have just filed papers through the courts for a custody hearing-that takes 6-8 weeks. we are worried about the environment that the baby is in-she has had her children taken from her and they were in the foster care system for a while. since there is no agreement reguarding the child at all, is there anything that would prevent us from going and getting him in ky. could that be considered kidnapping if the sister does not have any legal right to the child? we are worried sick and do not know what else to do. any help at all would be greatly appreciated.

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