In this case—namely, perpetual prohibition—does he become a mahram to her? No, even though the prohibition is perpetual, because it does not arise from one of the recognized causes; for the recognized causes that establish perpetual prohibition also establish mahram status, and they are three: blood relationship, marriage relationship, and breastfeeding.
Is he a mahram to her daughters? The answer is that he is a mahram to her daughters if he consummated the marriage with her, because they are his stepdaughters. He is a mahram to her mothers even if he did not consummate the marriage with her, because a wife’s mothers become unlawful to the husband merely upon the marriage contract, and they are his mahrams.
Fourth: the child is disavowed. But is it stipulated that he explicitly disavow the child, or not? The scholars differed concerning this. It was said: if he disavows him, the child’s disavowal is established; but if he does not disavow him, the child belongs to him. They cited as evidence the Prophet’s ﷺ statement: “The child belongs to the marital bed” (1). This child was born upon his marital bed, so he belongs to him.
Some scholars said instead that the child is disavowed merely by the completion of li'an, even if he does not explicitly disavow him. The child’s disavowal here follows from the li'an, just as he is not subjected to the prescribed punishment for falsely accusing her of adultery; rather, that punishment is waived consequentially. Likewise, the child is disavowed consequentially. This view is correct. Thus, the children of those who engaged in li'an during the time of the Messenger ﷺ were not ascribed to them; rather, they came to be called after their mothers, not their fathers.
Issue: If the child is ascribed only to his mother, how does she inherit from him? Does she inherit the share of a mother, or the share of both a mother and a father—receiving the prescribed share and the remainder as a residuary heir—or does she receive the prescribed share while the remainder goes to her nearest agnatic relative? There is disagreement among the scholars concerning this.