Issues with house quick deeded to me

My mother quick deeded her houses to me in a small town in Monahans Texas. THey are not worth that much, but I was going to try and sell them as she is no longer capable of the upkeep and such. While in the process of saleing them, it was found that the person that sold it to her, did not have the proper paperwork. That person signed for his wife, who was incapable of signing, but supposably he did not have or they cannot find the power of attorney for him. They both have passed on, but I still cannot sell the house as the title company is telling me that I need to find all of their children and get them to sign a warranty paperwork. I dont live in the same town and I keep getting court issues of upkeep and such. How can I either sell them or return them back to my mother, so I dont get stuck with the taxes and court issues? Thanks