Can parents marry a slightly retarded son who is not in a position to support his wife even though she accepts the marriage.

All perfect praise be to Allaah, The Lord of the Worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad, sallallaahu ‘alayhi wa sallam, is His Slave and Messenger.

It is permissible to arrange the marriage of the insane man and those who are like him such as the mentally deranged one. It may be even obligatory on his guardian if he needs that. If he has no money to spend from it on himself and his wife, then his father will be obligated to spend on him and his wife. Ibn Qudaamah said in Al-Mughni: "Whoever is obligated to keep him chaste is obligated to spend on his wife because he cannot keep him chaste except with that. It was reported that Imaam Ahmad said: 'The father is not obligated to spend on the wife of his son. But, that is apparently if the son is able to spend on her."

Allaah Knows best.