Property share

My Husband and his dad had estranged relationship. When my father in law passed away, we were not told about his demise. Anyways we made to the funeral and my husband being the eldest son performed the last rites. Now after some time my mother in law and brother in law told my husband that my father in law had disowned him before his death. My husband is not greedy about his property but we still tried our level best to mend our ties with the family. We called them but they won't pick our call. We also took our son to meet them but they were cold. They did no invite us to my sister in laws and brother in laws marriage as well. We moved abroad and after some years again tried to get in touch with them, but they stopped picking our calls after once. We now want to file a case for property as we find it very unfair on my mother in laws and my brother in laws behalf to cut ties with us in spite of our tries. My mother in law was a housewife all her life and my husband used t give his salary to her before we got married. Can we file a case on my sons behalf. Also can I take care of the legal part as my husband's job is very demanding and traveling to India can be difficult for him. Please suggest.