Is my family entitled to deprive my father's other wife and her daughter of their inheritance from my deceased father, on the pretext that he registered most of his estate in the names of family members before his death?

The mere registration by the father of his property in the name of his wife and some of his children, to avoid legal problems, without actual ownership that fulfills the conditions of a gift (hiba), does not result in their ownership of it. All that the father left behind is the right of all legal heirs according to their prescribed shares, including the other wife and her daughter. It is not permissible to prevent them from their inheritance, otherwise, they would be unjust, wrongfully consuming the wealth of others.