The share of my mother in the property of my grandfather

Dear sir, MY GF father had two wifes my GM was he first wife of my GF. My GM was died in 1970 later my GF got married anoter women. My mother has only daughter of first wife of my GF and second wife has 4 children(3 male and one female). he z the farmer and illetarate and got died in 2016. He has the total property of 50 Acers land. out of that 38 Acers are ancestral and 12 Acers are bought by him with income of ancestral property. He does not have any other source of income. Before the 6 months of his death my Gf register all his property to all the children and grand children of second wife. He did not give single acer to my mother. Could you let me know can my mother get equal right along with second wife children? and can we get equal right in both ancestral and self acquired?