A teen received a double graduation gift when he was presented with the keys to a new truck – before his military sister jumped out to surprise him after returning home to celebrate. Tryten Gavina from Barling, Arkansas, and his older sister, Elisa, were born just 18 months apart, and over the years they built up a strong bond while helping their single mom, Jennifer Knack. The siblings' father left the country when Tryten and Elisa were six and four, Jennifer said, so they leaned on each other for support while Jennifer did her best to raise them alone. After graduating high school, Elisa left home to begin serving in the U.S. Navy, which she saw as her best route of fulfilling her dream of becoming an anesthesiologist. With Elisa based in Walter Reed Medical Center, in Bethesda, Maryland, Tryten found his senior year tough, navigating the end of high school without his best friend. On his 18th birthday, on May 6, the teen said his only wish would have been to have Elisa home – so his sister began working on a way to return to Arkansas for his graduation. Jennifer had given her son two options, a truck as a graduation gift or a trip with mom, and with Tryten having chosen the vehicle, Jennifer knew she wanted to plan an extra layer to the gift.