Should she cut off her ties with her adopted brother who has left Islam (is an apostate)?

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Who are the mahrams in front of whom a woman can uncover?
A family adopted him because his family were bad people, and they gave him their name; what are the consequences of that?

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Who are the mahrams in front of whom a woman can uncover?
A family adopted him because his family were bad people, and they gave him their name; what are the consequences of that?

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