Transfer of late sister's share of ancestral property to brothers

My father died in 1997, we were three brothers and three sisters, mutation opened in 2009 of ancestral property in the name of the three brothers and my mother and panchayat, local body had relinquished sister's proportion in favor of three brothers without any legal formality, in 2013 my mother died, we got opened mutation of mother's proportion in favor of all six members of my family, one of three sisters died in 2014, rest of two sisters relinquished her proportion in favor of us but the question is this, how can we get the third sister's proportion in favor of us which is already opened in her favor?