Grave of the Fireflies (1988)

After the atomic bombs fall on Japan, two suddenly orphaned children must fend for themselves. Teenager Seita and his four-year-old sister, Setsuko, search through the rubble of their city for food, but in the middle of the war, it's almost impossible to keep themselves fed. As they slowly succumb to their hunger, the two children lean on each other for support, but not every story can have a happy ending.

Grave of the Fireflies is an anime movie featuring Tsutomu Tatsumi.

It is possible to buy Grave of the Fireflies on Apple TV and Vudu.