The Okiku doll

A Japanese doll kept at Mannenji temple in Hokkaido. In the story told about it, a family came to believe its hair was growing after the young girl it belonged to died.

The story, as Japanese Wikipedia gives it, begins in 1918. A 17-year-old in Hokkaido, named in the tellings as Eikichi Suzuki, bought his three-year-old sister a doll with a bobbed okappa haircut from a shop in Sapporo's Tanukikoji. The girl in the story loved it and slept beside it every night. The next year she died suddenly of a cold. The family forgot to put the doll in her coffin and kept it at the household Buddhist altar with her remains. In the story, its hair grew to shoulder length, and the family came to believe her spirit had entered it. Thersa Matsuura's Uncanny Japan podcast places the purchase at the Sapporo Exposition on 15 August 1918.

In 1938, Japanese Wikipedia says, the family moved to Karafuto and left the doll with Mannenji temple. After the war the brother gave it to the temple for good, as the dwelling of his sister's spirit, and asked for perpetual memorial rites for her. The doll is still kept there. English Wikipedia reports a claim that a priest trims its hair regularly.

The tellings disagree. Matsuura describes another version in which the temple took the doll in 1958, the girl has a different name, her father bought the doll instead of her brother, the father died before he could visit it again, and it was the monks who noticed the hair growing.

In 2010 Nikkan SPA! quoted a speaker who said the leading explanation is that the hair was set into the head folded in two and later slipped, leaving uneven lengths that look like growth. The speaker added that an examination could settle the question, but the temple has not given permission for one.