You didn't give any dates, so I don't know if the information I have for you is pertinent. There was a Don Pedro Jaramillo, aka Don Pedrito, (1829-1907) who was called the "Healer of Los Olmos". He lived in the south Texas area.
If this is your relations, there is a book entitled "Mystic Healers and Medicine Shows" that has a chapter pertaining to the lives of Don Pedrito and Dr. Mud. I hope this helps you.