Father would have to consent to the adoption. Definitely worth petitioning for custody if you feel that you and your family can care for the child.
Legally, probably not. Not unless they have legal custody of the minor's child.
The grandparents have no right to the child, only the parents can decide about adoption. If she does not want custody the father can get it.
Both biological parents have to sign their rights away or there will be no adoption.
Open adoption is when the biological mother/father, and their child are still allowed to meet and see eachother, even after the adoption process is complete. Closed adoption is when the biological mother/father of the baby can see their child for a year after the adoption. They can send pictures, letters, etc. After the one year, they have no contact with them, until the child is 18.
Yes, they can under extremely narrow circumstances such as the mother being coerced to release the child for adoption. If notified of a challenge they should contact an attorney who specializes in custody and adoption issues immediately.
their parents
The parents have assumed joint custody.
You can only give the child up for adoption if both parents agree. If he doesn't want that he can get custody and you will pay child support.
Yes it's always the parents decision what to do. The father have to give his consent though since it's his child too. Maybe he wants custody.
Neither, just guardianship.
On adoption, the Torah says that the child's status is determined by his birth parents and not adoptive parents.
No it is not. Adoption is permanent.