One day an old woman was washing her clothes by a stream and a giant peach floats down the water. When she took it home to show her husband and to share the peach, a boy popped out, claiming to be their son sent from the gods. Because he came out of a peach, the couple decided to name him Momotarō (桃太郎).
When Momotarō grew up he decided to go on an adventure, and he befriends a monkey, a rooster, and a bear. Together they fought oni (鬼; ghosts) on an island and claimed their treasures, which Momotarō then took home to his parents. They lived happily ever after.
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Informant had studied abroad in Japan and considers herself more Japanese than Chinese or American. She learned such folklore from her Japanese friends.