Validity of marriage when the spouses enter Islam

Q: I know a 24-year-old man who was Christian, but Allah guided him to do that which He loves and which pleases Him, and he embraced Islam in Egypt. He is an Egyptian and he has now left his parents, his wife, and his 3-year-old child, and traveled abroad in pursuit of a better future. However, he receives letters from his mother and sends her some money, saying that it is a way of maintaining the ties of kinship. Is it permissible for him to be in touch with and support his Christian mother, when he is Muslim? The brother also asks about returning to his wife, if she agrees and she accepts Islam. If he does, should there be a new marriage contract or is the contract (Part No. 19; Page No. 27) they first made sufficient? If she refuses to accept Islam, but agrees to live with him, is it permissible for a Muslim man to be married to a Christian woman? What is the consequence on the children, are they Christians or Muslims? He insists that he will marry a Muslim woman if his wife refuses to embrace Islam. We are trying to convince him to return to his wife for the sake of his child as they have now been separated, without a divorce, for four years. Please advise us and may Allah guide you and reward you with the best!

A: First: A son supporting his disbelieving mother is Wajib (obligatory); he has to be a good companion to her and be dutiful to her and maintain kind relations with her as far as he can. Allah (Exalted be He) says (what means): But if they (both) strive against you to make you join in worship with Me others that of which you have no knowledge, then obey them not; but behave with them in the world kindly The Prophet (peace be upon him) said to Asma' (may Allah be pleased with her), when she asked him about her mother, who came to visit her while still a Mushrik (one who associates others with Allah in His Divinity or worship), "Shall I keep good relations with her?" The Prophet (peace be upon him) said, "Yes, keep good relation with her." Second: If a husband embraces Islam and his wife does the same, they can continue with the same marriage contract as previously; they do not need to make a new one. Third: If the wife is a Christian who refuses to embrace Islam, it is permissible for the husband to stay with her, as the basic ruling is that it is permissible (Part No. 19; Page No. 28) for a Muslim man to marry a chaste woman of the People of the Book. Fourth: As for the children, they should follow the best religion of their parents. If one of the parents embraces Islam, the ruling is that all the minor children should become Muslims, as children follow the parent who has the best religion. May Allah grant us success. May peace and blessings be upon our Prophet Muhammad, his family, and Companions.