The Cradle Affair (揺りかご, Yurikago?) was a coup d'état staged by Xanxus and his Varia underlings to overthrow the Vongola Nono. The event happened at the Vongola Headquarters eight years prior to the Varia Arc.
Though the Varia managed to almost completely destroy the base, they were stopped when the Ninth froze Xanxus with the Zero Point Breakthrough. Just before he was frozen, Xanxus told the Ninth that he knew the secret of his adoption, and it was just then when Squalo first heard about it. When frozen by the Zero Point Breakthrough, Xanxus was inflicted with the signature scars on his face and body.
After Xanxus was frozen by Tsunayoshi Sawada during their battle, the spectators were reminded of the Cradle Affair and questioned Squalo. Squalo refused to talk and promised to keep to take the story to his grave.