Is it permissible to seek forgiveness with the intention of facilitating marriage for another person?

It is permissible to seek forgiveness (istighfar) with the intention of facilitating marriage for a brother, because a Muslim should present a need and an act of worship that brings him closer to God, such as the prayer of need (Salat al-Hajah (definition)). The request to facilitate marriage is a legitimate need, so there is no objection to performing acts of obedience to facilitate it. No specific act of worship or particular remembrance has been mentioned in the Shariah for facilitating marriage; rather, supplication (du'a) is beneficial for every legitimate request. It is good to increase seeking forgiveness for one's brother to facilitate his affairs.