Ibn Umar (Allah be pleased with them) reported Allah's Apostle (ﷺ) as having said this:
A person should not enter into a transaction when his brother (had already entered into but not finalised), and he should not make proposal of marriage upon the proposal already made by his brother, until he permits it.
Reference: Sahih Muslim 1412 b In-book : Book 16, Hadith 58 USC-MSA web (English) : Book 8, Hadith 3287 (deprecated)
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