Claim to property acquired by father sold to one son

My father was received property from govt. in return of property in Pakistan after India-Pakistan partition.My father sold property to my mother in 1998 to my mother & my mother sold the same to one of my younger brother in 2002 now recently when my mother expired due to cancer we came to know about it . Now we remaining 4 brothers and can claim for our part of property? Are we eligible for it? Some part of property is occupied by other three brothers but in name of only one brother.