Property mong step brother

Sharing of ancestral properties. my grand father died in 1950. his first wife died leaving behind two male childrens in 1930s. he married again. his 1st son died without marriage. 2nd wife has one male child. 2nd son got married in 1940s. after death of his father due to old age, he took over the family and brought up step son who was 15 years younger and looked after the step mother. my father purchased two of the properties in his name before the death of my grand father. there are few ancestral properties. no properties earned by my grand father. my father shared some properties with step brother in 1970s orally and used by them. no record created my father died in 1999 and my mother died in 2008. we are 5 male and 2 female married and living seperately. please advice the legal position of sharing the properties between my uncle and us at present situation my uncle disputing the share of properties used by him and us my uncle disposed some properties purchased in his name immediately after oral partition. this property was not shared to my father please advice