David Smith
24 when operation snake eater
He is a kind but old fashion person with family beliefs and a true Patriot
He was known as Unpredictable Cobra during snake eater when him and Naked Snake was sent kill their mentor the Boss.
After the events of Snake eater he went back to the States and retired. Till liquid ocelot showed up that's when he contacted EVA and he started a resistance to try stop him.

Travis Smith
19 when phantom pain happen. In 85 he joined a cryo test for United States leaving Diamond Dogs. He tried to find his sister Sarah. Who vanished. In 2005 he awoke in shadow Moses island with Paz who survived. They assisted Solid Snake take down Liquid and spared Sniper wolf. After he found Kaz him with Paz and Kaz recreated diamond dogs and helped Raiden in tanker mission. Eventually helping solid fight Liquid ocelot and his sister in mgs4

This is Sarah