After playing the "Forrest Gump" character of Lt. Dan Taylor, who loses both his legs in the movie, Sinise has made it a mission to help disabled veterans and their loved ones.
"There's something different about this part," Sinise said in an interview on ABC's "Good Morning America." "I've walked into so many hospital rooms and they look at me and they think I know what they're going through."
He started the Gary Sinise Foundation, a non-profit organization that raises money for veteran causes.
"After the injuries and all that, it feels like you can't go out in the world anymore," said Staff Sgt. Michael Irish. "All you want to do is be in a dark room and just sleep it off… and now with Gary and his organization helping us… to have fun and be yourself, that's very important to all of us."
Notable deaths of 2014 [PHOTOS]
Mindy Kaling mistaken for Malala Yousafzai