Litigation on property from uncle's wife of blood relation

Earlier my father's family is joint family. My father's brother borrowed some money and he died. After division among family, We have received the land against money borrowed from us by the wife of my father's brother. It was registered on my father's name in the year 2004 and we have built the house in that land 5years back. Now after 10 years due to some disputes among the joint family, sons of my aunty sent a lawyer notice to us "stating that the land was taken from her mother forcibly with her sign, showing the old original documents of land". We have not taken the notice, since it was an false litigation. Recently my father did my marriage and he is facing problem due to financial problems. He is having only this property to clears his debts borrowed for my marriage. Now we do not have money to keep a lawyer to defense the case. Will the case/notice against us valid?? Is there any chance of loosing our House?? If we keep a lawyer to defense the case against property and we won the case, is the money spent on lawyer will be given from the opponent?? Please give the valuable suggestion