Sinise has stayed in character since playing the role of platoon leader Lieutenant Dan Taylor in the 1994 classic. He established the Gary Sinise Foundation in 2011, which assists war veterans and their families. The three costars reunited for a multiday event at the foundation called Hollywood Salutes Heroes.
"Hadn't seen these old friends for too long." Hanks captioned the photo on his WhoSay account Thursday.
Hanks won an Oscar for his now iconic character, and some of the film's most memorable scenes are in the barracks of Vietnam with Lt. Taylor and Bubba Blue, played by Williamson.
Forrest Gump won six Oscars in 1995, including Best Picture, Best Director, and Best Actor. Sinise was nominated for Best Supporting Actor.
Hanks recently shared in a Q&A on Reddit that he gets a bit weepy when he watches a particular scene from the film. "When Lt. Dan introduced Forrest to his wife, with his titanium legs," Hanks replied, "I burst into tears."
Well, now we have, too. (E!)