Division of Property among family members

Respectd Sir/Madam, I am a female aged 24years got married one and half year back and It was a love marriage. Now I have a 7months old boy. My Parents didn't agree my marriage and not willing to maintain any relation with me. My Father is the only son of my Grand parents. Me and my younger brother (aged 22 years) are the offspring of my parents. We have three and half acres agriculture land at my native place and the whole property is on my Grand Father's name who expired in March 16, 2013. My Grand mother (mother of my father) is alive. My father is not willing to the division of the agriculture land. He has been enjoying the land with out giving any share of the crop to me. He is not looking after his mother and totally ignored her. If I and my grand mother go to civil court what will be our share in the respective agriculture land. Please kindly make me know what will be my grand mother's share and my share in the inherited property. My father's and my younger brothers share in the property. Thanking You Lavanya Maradani.