My Dad wanted to be separated to my mom

I need your legal advice please.  My parents are separated for 18 years.  My mom went abroad and my Dad declared that she is dead to have another marriage.  My dad has 3 wives after my mom and all of them he got children. At the end my dad went to my mom and ask her to be with him after his so called disposal to the 4th wife.  My dad promised her good life, promise my sister to quit his job and move to our old house and manage the business and I with my family he convinced me to stay also at the same house for me to save more money.

Now, literally, he wanted my mom to leave the house and maybe he is going to get the 4th wife back to house.  My mom is already old and she quit her job from abroad to be with my dad.  He ask my mom he want to be single again.

What should we do? we do not want our mom to leave the house.

Don't leave the house then. It's their house, and a conjugal property.

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