Required my mother's signature?

My house is going to be sold and the money will be distributed by signing a legal agreement in court . It will be distributed among me(as my father is no more) and my 3 uncles. Now I don't want my share and I will mention this in that agreement. My question: Is this agreement requires my mother's signature or my signature is enough as my mother don't want to come for signature. On what ground I can tell that I will sign instead of my mother? Please note that not taking the share is joint decision taken by me and my mother. Religion:Hindu