I Am Searching for Prewitt Descendants of Comanche CO TX John and M

I am searching for Prewitt descendants of Comanche Co, Tx. John and Mary J. Prewitt were my GGrandparents. I believe John had two brothers, James and William S. Prewitt. Also looking for descendants of Samuel Henderson and Lela Belle Gilbert Vandeventer as well as John William and Katy "Caroline" Hart Howard of Collin Co, Tx.