Sharing property

My dad has 3 male and 2 female siblings, so including my dad there are 4 sons and 2 daughters to my grand dad. there is only one small house, and a little agricultural land. about 15-18years ago, in presence of village elders, there was sharing process. as we are 3 daughters to my dad and only my dad and mom took care of my grand parents, the house was given only to my dad. and the agricultural land was shared btw all 4 sons of my grand parents. as the house was very old and because of the heavy rain, some part of the house collapsed. and we reconstructed almost 50% of our house and spent approx 3 lakhs. we lost our dad in an accident 4 years back, and now my uncles, siblings of my dad are asking the share in our house. and one of my uncle keeps coming to our house when my mom is alone and starts fighting with her. and there were no registration/legal document done during the last sharing of the assets, 15-16 years back. Can you suggest how we can tackle this problem, correctly/legally?