She does not have any male relatives on her father’s side; can her mother’s husband or her brother through her mother be her wali (guardian) for the purpose of marriage?

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Check below answers in case you are looking for other related questions:
Marriage without the woman’s wali (guardian), and innovated divorces (talaaq bid‘i)
Marrying a second wife when one is not able to take care of two wives

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Related Answers:
Is it correct for the husband’s father to be a witness to his marriage contract?
She wants to get married but her sons refuse
She unknowingly married her daughter to a mushrik, and she has three children from him, and she is asking about the ruling
Marriage without the woman’s wali (guardian), and innovated divorces (talaaq bid‘i)
Marrying a second wife when one is not able to take care of two wives

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