Grave of the Fireflies/Hotaru no Haka

Summary:
On the final days of World War II, 14-year-old Seita and his four-year-old sister Setsuko are orphaned after their mother is killed during an air raid by American forces in Kobe, Japan. After having a falling out with their aunt, they move into an abandoned bomb shelter. With no surviving relatives and their emergency funds and rations depleted, Seita and Setsuko must struggle to survive their hardships as well as those of their country, which is on the losing end of the war.

Songs:
Opening Theme:
"Setsuko and Seita" by Michio Mamiya

Ending Theme:

"Futari" by Michio Mamiya 

Related Links:

Wikipedia - http://en.wikipedia.org/wiki/Grave_of_the_Fireflies

Anime News Network - http://www.animenewsnetwork.com/encyclopedia/anime.php?id=152 

Watch:
http://www.veoh.com/watch/v1353909hKkM637E