The ruling on one who has intercourse with his fiancée before the marriage contract

This is a message received by the program from two Sudanese questioners residing in Madinah, namely: Mukhtar al-Nur al-Din and Saif al-Din al-Tayyib. They say: We ask you to issue a ruling on a man who had intercourse with his fiancée before the marriage contract was concluded, and she became pregnant from him. She informed her fiancé, and he hastened to complete the marriage contract. Then Allah granted them a child. What is the ruling on this child from the perspective of the Shari'ah, even though the father acknowledges him?
Answer: This child is a child of zina; because his intercourse with her before the contract was completed is abominable and zina, he is not attributed to him and does not become his son. Rather, he is attributed to his mother, or attributed to 'Abd Allah or 'Abd al-Latif, or 'Abd al-Malik, by way of concealing it for him in the future.
The point is: he is not attributed to his father; because he is a child of zina, but he is attributed to his mother and added to her. And both of them must repent, the woman and the man must repent to Allah (Glorified and Exalted is He) and renew the marriage; because the contract took place while she was pregnant from zina. So it is obligatory to renew the marriage after she gives birth. Her guardian renews it after both of them repent to Allah (Glorified and Exalted is He), and we ask Allah for guidance and success for sincere repentance for everyone.
The presenter: And if he has not renewed the contract until now, does he separate from her?
The Shaykh: He must separate from her and refrain from her until he renews the marriage. He must refrain and stop his contact with her until he renews the marriage with her guardian. Yes.
The presenter: May Allah reward you with good.