Thanks for the responses from Samit and Lakhani. They are of great help.
So in simple, couple of possibilities is there in future as follows:
1) If my grandfather didn't made a will (i.e) my father got this lands by succession, then we all have the right to claim the share in property and my younger brother can’t do anything by his own. Can my younger brother obtain power of attorney from my father and act on his own without the consent of other family members?
2) If my grandfather made a will so that property goes to my father, then my father had every right to give (either as gift or transfer) that to anyone he likes ( his younger son) during his lifetime without taking any consent from others in family. Am I right?
3) If my grandfather made a will so that property goes to my father, then my father made a will so that goes to his younger son, then his younger son is the sole owner of that property ? Am I right? In that case what is the validity of fathers will as this is ancestral property?
Without disturbing the harmony in family, is there any way to sort this kind of scenario so that everyone gets their share in ancestral property. Here father and younger son act smart and do the things without the knowledge of others in family.
Can you please provide the weblink of original copy of HAS, 1956