Are the sons of her first husband mahrams to her and her daughters from her second husband?

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Check below answers in case you are looking for other related questions:
Should he marry a woman who got divorced for his sake?
Is my father a mahram to the wife of my half-brother through my mother?

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Women who are forbidden for marriage because of kinship
Can he marry his paternal cousin’s daughter?
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Should he marry a woman who got divorced for his sake?
Is my father a mahram to the wife of my half-brother through my mother?

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