Sunan Ibn Majah · Hadith 1941
The Chapters on Marriage - كتاب النكاح
حدثنا يحيى بن حكيم، حدثنا يحيى بن سعيد، عن عبيد الله بن عمر، عن نافع، عن ابن عمر، قال قال رسول الله صلى الله عليه وسلم " لا يخطب الرجل على خطبة أخيه " .
It was narrated from Ibn Umar that: the Messenger of Allah said: “A man should not propose to a woman to whom his brother has already proposed.”
Gradings are classical jarḥ-wa-taʿdīl, name-matched to a rijāl index (not individually re-verified).