Gillaspie married Susan Faris of Walker County; they had seven children. During the Mexican War he raised a company for the First Regiment, Texas Mounted Volunteers, for service under John C. (Jack) Hays. With the outbreak of the Civil War Gillaspie again raised a Walker County company for the Fifth Regiment, Texas Infantry Volunteers, and was stationed on Galveston Island. Gillaspie was superintendent of the Texas State Penitentiary at Huntsville from 1850 to 1858 and again from May 1867 until his death, on October 3, 1867. He was buried in Oakwood Cemetery, Huntsville. The monument at his grave lists the personnel of the various units that he commanded during three wars.
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