Will deed

My father wants to make a will. He is 80+ and my mother is 75+ years old. We are three sisters. Me and my father work together and have a partnership firm. We have total of 6 property. 1. Registered property under the name of Father and Mother 50% each. 2. Registered property under my name. 3. Registered property through general power of attorney by my father under my name. 4.Registered property under my elder sister and mother's name. 5. Through GPA, Will, Agreement to sell, Affidavit and possession letter under my and my mother's name 50% each. 6. Through GPA, will, agreement to sell and purchase, Affidavit and possession letter under my father and mother's name 50% each. Now my father wants to make a will and want to give property number 1&2 to me, property no. 3&4 to my elder sister and property no. 5&6 to my eldest sister. 1.Can he make a will for the property which is already under my name. 2. Can he make a will for my mother's share in the property. 3. Can he make a will for the property purchased through power of attorney under my name. 4. If he makes the will as per his wish Above will it be valid or will it get rejected totally.