then they must be separated and she becomes permanently unlawful for him; everything that has already taken place is treated as a doubtful marriage, while the children remain legally his.

So long as there is only a report that some nursing occurred—and the manner and number of sucklings are unknown—the default assumption is that the marriage continues in force: she is still his wife unless nursing of the type that renders marriage unlawful is conclusively proven.
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A woman’s beautification after her waiting period has ended

Question: May a woman whose ʿidda has ended—whether the waiting period was for divorce or for the death of her husband—adorn herself when suitors approach? If this is allowed, does it not conflict with the Qur’anic verse that a woman is not to display her adornment except to her husband or to her maḥram relatives?

Answer: Once her ʿidda from divorce or widowhood has ended, a woman may beautify herself in the customary, lawful manner, as indicated by the Almighty’s statement: “There is no blame on you regarding what they do with themselves in an honourable manner” (al-Baqarah 2:234). That is, she may use whatever is customary and free of temptation or harm—such as kohl, henna, and attractive clothing. This, however, does not mean that she may appear before unrelated men wearing that adornment. It is forbidden for her to reveal any of her beautification to non-maḥram men, whether or not she has completed her waiting period. A Muslim woman is prohibited from standing before men in a way that draws attention through the adornment of her body or her clothes.

This does not contradict the verse: “And let them not display their adornment except to their husbands” (al-Nūr 24:31), because the verse refers to adorning herself inside her home and among women. As for going out before men and exposing her adornment, that is never permissible—neither for her nor for any other Muslim woman.