Praise be to Allaah.
The wali may appoint
someone else to take care of the marriage of the female relative under his
care, whether he is one of her relatives, such as her maternal uncle, or
Ibn Qudaamah (may Allaah
have mercy on him) said in al-Mughni (7/14): It is permissible to
delegate guardianship in the case of marriage, whether the wali is present
or absent, because it is narrated that the Prophet (peace and blessings
of Allaah be upon him) delegated Abu Raafi’ with regard to his marriage to
Maymoonah, and he delegated ‘Amr ibn ‘Umayyah with regard to his marriage to
Umm Habeebah. And because it is a contract of exchange, so it is permissible
to delegate it, just as it is permissible to delegate to others in matters
of buying and selling. End quote.
It says in Fataawa
al-Lajnah al-Daa’imah (18/103): The shar’i form of the marriage contract
includes the proposal of the wali or his deputy, and the acceptance of the
husband or his deputy, and that should be in the presence of two witnesses
of good character. End quote.
Based on that, the marriage
contract which was done in this case by the maternal uncle acting as the
brother’s deputy, is a valid marriage, and it is not essential that the
brother be present on the wedding day.
And Allaah knows best.