What legal papers would I need? My sister in law tried to give her son to the babysitter said she didn't want him anymore. She is always in and out of jail and her mother cares for the baby she is getting too old for young kids, we want him and are family. When she gets out of jail we are going to have her sign him over to us we will give him everything he needs and hey he'll have brothers! But I need to know if she can sign a paper stating she is giving us custody or if we need a legal document

She can not just sign a paper you write up. First where is the father, since if she does not what the child, the father has the first right to the child legally.

Next you will have to get legal guardianship of the child though the courts.

You need a lawyer. Adoption is a complicated process and there is no 'piece of paper' that will legally accomplish what you want.

she can not just sign a paper you write up. First where is the father, since if she does not what the child, the father has the first right to the child legally.

next you will have to get legal guardianship of the child though the courts.

The father is an illegal and wants nothing to do with him.

the father is an illegal and wants nothing to do with him.

What the father wants is irrelevant. He will have to be a part of the process