What are the legitimate and legal rights of a woman and her child from a man who married her after she became pregnant by him, and he refuses to acknowledge the child?

Adultery is a grave sin, and its perpetrator must repent from it. The child resulting from adultery is not attributed to the adulterer but rather to the mother. If the marriage contract was concluded before the delivery of the pregnancy, scholars have differed regarding the validity of this marriage. The Hanafis and Shafi’is deem it valid, while the Malikis and Hanbalis consider it invalid. It is preferable to renew the contract with its conditions.