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Tear Jerker: Barefoot Gen
The Anime Movie. The whole Godamn thing.
"Father, are you out there? Eiko? Shinji? The baby's here, everybody! Can you see her? It's a girl! You were wrong Shinji! It's a girl! What's happening? Why? Why? Why? Why?! She's the prettiest girl in the whole wide world, and you never got to see her."
The mother picking up her newborn daughter and raising her in the air slowly showing her the destruction of the bomb. "Take a good look around little one. You see? This is the war that killed your father, remember it."
Also, when said baby girl dies, just as the two boys come back with food.
The live-action adaptation has the father and Shinji, buried in the weight of their crumbled house, spending their final moments singing.
The soldier carrying Gen on his back to get medical attention, passing by a few wells with bloated corpses inside. The soldier tells Gen that they'd ran into the water, thinking it would save them from the fire.
That there is a boy and his little sister. He died trying to save her. And that woman there tried to protect her children by hugging them close to her. All in vain.
Most of the random civilians we see post-bombing are worth quite a few tears. The woman who thinks her son has reincarnated into a swarm of flies, the gang of orphan boys who all watched their own families die, the adolescent girl who wanted to be a dancer survives but with horrible burns on her face—she'd watched her mother die and walks among the corpses, checking their teeth for her mother's gold teeth, so she can bury her by her father...