please what can i do??

My mother pased away, unexpected she has no will or anything nameing anyone head of estate or anything like that. She only has two kids. Myself and my older sister. She passed as a result of medical malpractise. There is a lawsuit in the process. My sister and i along with our Grandmother agreed to start a lawsuit. My grandmother had my sister and i sign some kind of paper that made her estate adminisrator. Sence then my grandmother has stoped talking to us and said we can't have anything to do with the case. Is there anything we can do? Noone ever explained to us what those papers ment. My grandmother told me I had to sing them because there could only be on head of estate and it had to be her or my sister (who is older). Then told my sister she needed to sign them because she couldnt affort to pay the lawyer fees, or make trips back and forth to take care of things. I don't even know if the paper we sign means what she is now saying. To me it looked like the paper said that we were entitled to a will or funds but was signing over to my grandmother. But there was no will or anything to take. Except the pending lawsuit. What do these papers mean and is there anything we can do about it???????

Have a lawyer intervene and see what is happening--it should only cost a modest amount.

You may learn that everything is not proper.