1) were you served with copy of the suit [proceedings before court grated stay ?
2) have you filed detailed reply mentioning that property was purchased from your own funds ?
3) has your father in law enclosed any evidence regarding transfer of funds for purchase of property ?
4) if father in law is claiming share in property they have to pay court fees on market value of their share
5) it is necessary to peruse the suit filed by your in laws to advice further