Memorial Day (2011) on Netflix

Plot summary

Thirteen-year-old Kyle Vogel comes across his grandfather Bud's footlocker from World War II during a game of hide and seek, and everyone tells him to put it back. Bud has never spoken about the war. Instead he makes Kyle an offer: pick any three items from the locker, and Bud will tell the story behind each one, including a Walther P38, a grenade fragment, and a photograph of Bud with his friend Jack O'Hara. The stories reach back to Western Europe, where Bud served with the 82nd Airborne Division, and forward to Kyle's own tour in Iraq with the 34th Infantry Division.