Is it permissible for a mother to perform Hajj using the money of her minor son, who possesses sufficient funds for Hajj?

The child's money is his property, and the mother is permitted to partake of it reasonably. She is also permitted to perform Hajj from it if her child grants her permission after reaching maturity. Hajj is not obligatory for the mother if she does not possess the means, and if her child possesses it, it is not obligatory for her unless he willingly offers it to her.