It was narrated from 'Amr bin Shu'aib, from his father, that his grandfather said:
"The Messenger of Allah said: "Whatever is given as a dowry or gift before the marriage, it belongs to her. Whatever is given after the marriage belongs to the one to whom it was given. And the most deserving matter for which a man is honored is (the marriage of) his daughter or sister."
English reference: Vol. 3, Book 9, Hadith 1955
Arabic reference: Book 9, Hadith 2031