If a husband sells a house built with money from the sale of his wife's jewelry, is the house then exclusively the right of the wife, or does the son from a divorced wife have a share in the inheritance, knowing that the husband intended to return the value of the jewelry to his wife, and the value of the jewelry is determined by weight as a debt owed by him?

If the jewelry was a loan, you must return its equivalent, and the house does not belong to your wife. However, if you took the jewelry to trade with it for her benefit, or to buy a house for her with its value, then the house would be entirely hers if it was purchased with the value of her jewelry. As for the son from the second wife, he is an heir, and none of the heirs has the right to take anything from the inheritance until after the debts are paid, for debt takes precedence over the right of the heirs.