Partition Deed done in 1993.

My father (J) and his sister (B) are children from the first wife of my grandfather. After her death, my grandfather married again and had 4 children( 3 sons(A) (S) (V) and 1 daughter (S)) from his second wife. My Grandfather signed a partition deed in 1993 in which he gave an equal share of his farmland to (A)(S)(V) and slightly bigger share to my father (J). My Grandfather inherited the property from my great Grandfather. The partition deed is registered and no consent was taken from both daughters. In the partition deed, after declaring all the shares there is a clause about left out property that was in the name of my Grandfather that says that after his death his share (0.53 hectare) will be divided equally between (A) and (S) his sons from second wife. Later, my grandfather acquired 0.80 hectares and his share grew to 1.24 hectares. He died in 2008 and in 2012 his name was struck down in 7/12 and his 1.24-hectare property became co-owned property in which all 7 remaining legal hairs are listed. The mutation notes that this was done as per the succession act which states that the property of intestate dying should be divided equally between all the legal heirs. Because it is joint farmland and my father's name is on 7/12 it including other legal hairs can he claim a share in the money generated by this farm? Currently, (A) and (S) has given out the land on lease and they are pocketing the money they are earning from it without sharing it between all the co-owners. Also what about the share of my father's (J) mother. I can't help but judge that my father has been robbed out of his mother's share unlike his brothers from another mother who will inherit their mother's share.