House in chawl my uncle claims his share

my father owns a house in chawl in santacuz west Mumbai all proofs of my dad like ration card light bill photopass all BMC rent submitted on my dad's name . the matter is my uncles name is on ration card and he says he will claim his share on that house I want to know is that possible . how can we stop first before he claims and complaint or anything else ? please reply a serious matter .