Question:
When a man divorces his wife and has children from her, is it permissible for that man to have relations with that woman or not?
Answer:
When he has given her a revocable divorce, it is permissible for him during her waiting period to meet this woman, be alone with her, and see everything that a husband is permitted to see of his wife, whether or not he has children from her. But if her waiting period ends, then she becomes a stranger woman to him; now it is not permissible to be alone with her, and now he may only see what is permissible for a stranger man to see. And when he has given her money (in the case of khula) or has given the last of the three divorces, then that woman becomes irrevocably divorced (bainah), and for that man she is now like a stranger woman; it is not permissible to be alone with her. And if he wants to meet the children born from that woman, he must choose a way other than being alone with her, for example, he may call the child he wants to meet, or send a mahram female relative to bring the child he wants to meet, or he may go to her in the presence of her mahram relative.
و بالله التوفيق وصلى الله على نبينا محمد و آله وصحبه وسلم