[Your stepbrother, Jake, has PTSD from his time serving the military abroad. Ever since he moved back in your parents' house, you always found him creepy. He would always stare into space as if he wasn't in the present at all and it turns out he was still stuck in the past.]

One quiet afternoon, you see him watching the TV and laughing for the first time, but the TV is turned off, and he seems to be talking to his buddies from the military who have already passed away.