Narrated by Sayyiduna Abdullah bin Amr (may Allah be pleased with them both) that the Noble Prophet (peace and blessings be upon him) said: Any woman who marries for a dowry, a gift, or a promise, then whatever is given before the marriage contract will belong to the woman herself, and whatever is given after the marriage will belong to the one for whom it is given. It is daughters and sisters because of whom a person becomes most deserving of honor.
Hadith Takhrij«حديث حسن، أخرجه ابوداود: 2129 ، (انظر مسند أحمد ترقيم الرسالة: 6709 ترقیم بيت الأفكار الدولية: 6709»
Brief Explanation
Benefits: … By "promise" is meant that whatever things the prospective husband promises to give.
The meaning of the first part of this blessed hadith is that whatever is given to the guardian (wali) or agent (wakil) before the marriage contract, in reality, belongs to his daughter, and whatever is given to anyone after the marriage contract, it will belong to that person.
The meaning of the last sentence of the blessed hadith is that people should honor their brothers-in-law and sons-in-law.