Willaim A. Earp married Nancy Wyatt in Jefferson, Texas. In 1861, William Earp enlisted Co. C, 32nd Texas Cavalry, Col. Richard P. Crump's Battalion at Jefferson TX. The 32nd Texas was consolidated with Col. George Sweet's 15th Texas Dismounted Cavalry in 1862. Col. Sweet's 15th Dismounted Cavalry, Col. John L. Camp's 14th Texas Dismounted Cavalry and Col. Locke's 10th Texas Dismounted Cavalry were moved east of the Mississippi River where they were placed in Ector's Brigade, Army of Tennessee.

Pvt. William Alexander Earp was a cousin of Capt. Alexander and Col. C.R. Earp of the 10th Texas Cavalry. William A. and Nancy (Wyatt) Earp are buried in Jenkins Springs Cemetery in the Wyatt family plot in Brown County Texas.

Three other members of Col. Sweet's 15th Texas Dismounted Cavalry are also buried in cemeteries in Brown County Texas. Brooks W. Lee, of the historic Lee family of Virginia, enlisted in Col. Sweet's 15th Texas Cavalry and is buried in Lee Cemetery at the site of Camp Collier in Brown County.

In January 1862, Brooks Lee was furloughed from the 15th Texas Cavalry before the regiment left Texas and was made a recruiting officer for Col. J.E. McCord's Frontier Regiment in Gatesville and in Brown County. In 1842, Brooks Lee was the son-in-law of Leonard "Len" Williams, Texas Indian agent appointed by President Sam Houston in 1840. Brooks Lee was the scout who directed Len Williams to Buffalo Hump's Penateka Comanche Indian camp in what is now Coleman County in order to invite the Indians to the Techuana Creek Councils near Waco.