Is it permissible for my husband to deduct from his sons' inheritance what his first wife forcibly took from them, so that he may then distribute the remainder fairly among all the children?

The British law that mandates giving the wife half of the husband's property upon divorce is an unjust law, and it is impermissible to seek judgment by it. What the wife has taken under this law is considered a debt upon her that must be returned, due to the Prophet's (peace be upon him) saying: "Whoever has wronged his brother, let him seek his forgiveness." If the children are adults and agree to take the money, they must be informed that this amount will be deducted from their share in the inheritance. If they do not return the money, this should be recorded in the will for offsetting. However, if they are minors, he does not have the right to write such a will unless the money has been preserved in their names and is not disbursed to them until they reach adulthood and maturity.