Diapa Young was the daughter of Francis Young b. ca 1813 TN, d. 1864 Bastrop Co., TX and Sarah b. ca 1815 NC, d. after 1866. According to my source they were married Dec 16, 1879 Bastrop Co. I can send via email photo of Diapa and her sister Paralee [b. 22 May 1842 Benton, AR, m. Joseph Franklin Beach Apr 1, 1858 Bastrop Co., TX d. Aug 10, 1916, bur. Briggs, Burnet Co., TX] as elderly ladies.
I have no further information on Diapa and Robert Aiken, though if I find something in Texas deaths I will let you know.