Land issue

My father bought 1-acre land from his cousin's sister 10 years ago just on the basis of bond and letter of sellings with witnesess signs on it but did not go through with the registration process. All these years it's on their name but we were doing all the farming activities in the land. Now if we go and ask them for the registration they are asking for more money indirectly. There is another issue linked to this matter. My father married twice and divorced first wife and married second. There was no proper document that says they are divorced except the witnesses who were there and decided when they were separated. Now she is bringing a document saying my father wrote half of that one acre to her with a sign on bond paper which is not my father name till now. When we ask the current land owner to register it in our name they are saying they will register it equally to both wifes because they dont want any problems in the court with second wife. My mom is a daily wage labour and I have a brother and younger sister to get married. We dont have any money except that land but no one showing mercy on us and their greed becoming bigger everyday. Please advice me.