Can my father claim share in my mother's property

My father left my mom, my 2 young sisters and me in my childhood by torturing us without even a divorce with my mom and married a different women. My mom and me with lots of efforts purchased a sight. He was in the same campus, he saw us that we are struggling and he stated that he will support us in creating small compound for the sight. Now he is behind our sight and asking for money. We are muslims. If their is any way to get out of this problem and ask for our shares which he did not give till date? He never came to us in our childhood to see whether we are alive or dead and now torturing.