Tax saving

My mother has sold a property of Rs.25lacs which was actually purchased in 1981 for Rs.5000. After calculation there is a hefty amount of tax which is to be paid they are not interested in buying another property and we cannot even invest in capital bonds as six months have passed. What should i do to save tax. And one of the CAs have advised that it would be ok to take risk and not file the return as she has never been an assessee till now. What should i do? Please guide.