Can a disbeliever be regarded as a mahram for his Muslim sister when travelling?

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Check below answers in case you are looking for other related questions:
Who are the mahrams in front of whom a woman can uncover?
Ruling on a man doing ghusl for his mother

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Related Answers:
Sitting with husband’s relatives and shaking hands with them
Uncovering in front of the husband’s father through radaa’ah
Do women need to cover in front of a child who is five years old?
Who are the mahrams in front of whom a woman can uncover?
Ruling on a man doing ghusl for his mother

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