What is the ruling regarding a Muslim girl who cohabited with a Christian man without marriage, then left him and married a Muslim man without informing him of her past, and does she become permissible for her Muslim husband after he learns the story, and what is the ruling concerning the children with her Muslim husband?

What the girl committed is a grave sin, and she must repent and seek forgiveness. It is permissible for a Muslim man to marry her if she repents and reforms. She is not obligated to inform the suitor about her past. If children are born within the marital bed of the Muslim husband, they are his children. As for children born out of wedlock, they are attributed to their mother. It is permissible to spend on them and raise them, but it is forbidden to adopt them.