It is not correct to draw an analogy between donating blood and breastfeeding to prove that someone is a mahram

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Check below answers in case you are looking for other related questions:
Is the husband of her husband's daughter a mahram for her?
The wife’s grandmother is a mahram to the husband

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Related Answers:
Can she marry her mother's half-brother?
Marrying the sister of his ex-wife
Is there such a thing as a temporary mahram?
Is the husband of her husband's daughter a mahram for her?
The wife’s grandmother is a mahram to the husband

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