I Agree With Everything In The Summons Against My Brothers And I. Do I Need A Lawyer?

The situation is my brother A. handled my mother's estate and he hid property from my sister and other brother M. and me. My sister discovered this when a realtor called her about the property several years later. Anyway, sister is taking the matter to court and I am one of the parties to the lawsuit -- she wants to sell the land on open market,dividing the cash profit equally between us four siblings and she wants brother A to pay her legal costs. Brother A had wanted to buy out other siblings at below market price. I agree with everything set forth in my sister's summons. Do I even need to hire an attorney if I agree with her wishes?