Long before One Piece episode 1053, Sanji was born into the Vinsmoke family, the ruling family of the North Blue’s Germa Kingdom. He was born on the same day as his three brothers, being the third son of the family and making him the kingdom’s third prince. Princess Reiju, Prince Ichiji, and Prince Niji were older than him, while Prince Yonji was his younger brother.
Sanji’s father, Vinsmoke Judge, had planned to genetically enhance all three of them before their births to give them superhuman abilities without emotions. The plan aimed to turn them into perfect super soldiers for the future, courageous in the face of death and uncompassionate in the face