property ownership

I am asking for a legal advise. My aunt bought a property sometime in 2004 in a prime lot in Malate area. She named it after me yes land title and she pays the tax and she had me signed a power of atty that she has d right to sell it. A few years back we had some differences and wanted to sell the house. And since we are not talking i did not sign any paper pertaining to the selling of the house. My question is can she sell the house and lot even without my signature appearing on the deed of sale? Is the power of atty still valid? She wanted me to sign as the lot is really being bought for a good price but since I am mad at her I am not signing any paper. What can she do to sell the property without having me in the picture. Thank you very much.

an SPA is valid until it is revoked. however, if it is too old, the BIR and RD normally ask for a new one.