Is a father considered sinful for depriving his stepdaughter of the villa he wrote for his biological children and their mother, and must the children distribute the villa according to Islamic law to alleviate their father's torment?

If the father intended by the sale to defraud some of the heirs, then this sale is not valid in Islamic law, and he is not permitted to do so. The children and wife must return the villa to the inheritance so it can be distributed among all heirs. However, if the sale was genuine, then the price of the villa is considered part of the inheritance and must be returned to the general estate to be divided, while emphasizing the seriousness of inheritance matters and the necessity of referring them to the Sharia courts for investigation before distribution.