Sahih Adab al-Mufrad

Sayyiduna Anas (may Allah be pleased with him) says: One day I came to serve the Prophet (peace and blessings of Allah be upon him), and only I, my mother, and my maternal aunt Umm Haram were present. The Prophet (peace and blessings of Allah be upon him) came and said to us: "Shall I not lead you in prayer?" And it was not the time for obligatory prayer (meaning he wanted to offer a voluntary prayer). So one of the people said: Where did you make Anas stand? It was said: Anas was made to stand on the right side, then he led us in prayer. Then he supplicated for every good of this world and the Hereafter for the people of the household. Then my mother said: O Messenger of Allah! This is your humble servant, please pray to Allah for him as well. So he prayed for every good for me. The last words of your (peace and blessings of Allah be upon him) supplication were: «اللهم أكثر ماله وولده ، وبارك له» "O Allah! Increase his wealth and children and bless him in them." (This means that if the children are righteous, there is no better wealth than this, and one should pray for its blessing.)