[1] Through his daughter Margaret Lampton, he is the great-grandfather of author and humorist Mark Twain.
[1] Casey helped to establish schools in Green and Adair Counties as an early pioneer in the state.
[3] Casey was a prominent landowner in the area, owning over 600 acres and a farm with horses, cattle, and sheep.
[4] In 1792, Casey was commissioned as Lieutenant Colonel of the 16th Regiment of the Green County Militia, serving during the American Revolutionary War in a company of soldier settlers.
[7][1] Later in his life, Casey donated a tract of his land to become the first Presbyterian church in Adair County.