How should one deal with parents who differentiate in their treatment of their children and impose their opinions without consulting them, especially given that one of the parents is an Azhar scholar?

It is obligatory for parents to be just between their children and not to show love and affection to some of them to the exclusion of others, because Allah Almighty says: "Indeed, Allah orders justice and good conduct and giving to relatives" [An-Nahl: 90], and because the Prophet, peace and blessings be upon him, said: "Fear Allah and be just between your children."