Keepsake, also titled Memento or Posthumous Child, is a short story featured in the collection Venus in the Blind Spot.
Plot[]
Ishikawa Toyoji is a samurai who has recently re-married following the death of his first wife, Lady Suzu. Nine months after her death, Ishikawa's servants hear the sound of a crying baby coming from her tomb. They find that she has somehow given birth to a baby boy despite being dead. Ishikawa is deeply disturbed, despite his servants assuring him that it's not unheard of for a dead woman to have a child. He names the baby Manjuro.
Ishikawa's new wife Lady Mitsu has just had her own child and refuses to care for Manjuro. So her maid, Lady Tane, agrees to raise the baby. Ishikawa wonders how Lady Suzu could have conceived, since she was infertile when she was alive. He took Lady Mitsu as a concubine so that she could produce an heir for him. Lady Suzu wanted to raise the child as her own, but Lady Mitsu wouldn't allow it. She convinced Ishikawa that they should poison Lady Suzu and marry after her death.
Three years later, Manjuro has grown into a grotesque, corpse-like child. The local children won't have anything to do with him, and his half-brother Shinnosuke is terrified of him. One day, after Manjuro upsets Shinnosuke, Lady Mitsu ties Manjuro up and violently beats Lady Tane for not disciplining him. Ishikawa walks in, and Lady Mitsu accuses him of having sex with the dying Lady Suzu. Lady Tane reveals she knows what happened, and that the conception took place after death. Ishikawa is forced to admit she's right. While Lady Suzu's body was awaiting burial, she temporarily revived and begged Ishikawa to have a child with her, so he obliged. Manjuro has somehow freed himself, and appears in the doorway, causing Lady Mitsu to scream in terror.
Shortly afterwards, Lady Mitsu dies - seemingly from the shock of the truth about Manjuro's birth. Ishikawa marries Lady Tane, but nine months after Lady Mitsu's death, the servants hear a baby crying within her tomb.