Legal Question in Family Law in California

Well, first off, she would be guilty of statutory rape.

Assuming no one prosecutes for that, then it depends on if and when someone asserts the boy's fatherhood. He can't assert it until he is 18 unless his parents assert it for him. The mother can assert it at any time, as can the child. If he and the mother both want to identify him as the father, they file a Declaration of Paternity while the baby is still in the hospital, or with the Secretary of State at any later time.

If and when anyone asserts in court or by declaration establishes he I the legal father, then the law treats them EXACTLY as if they were divorcing parents as it relates to the child. Child support, visitation, custody, and anything else to do with the child is treated by the law exactly the same as divorcing or divorced parents. All the details of that are too much to go into without a specific question