Her father has it......that's it. This fandom puts more thought into the story than Oda himself. No one is born with grand ambition, but you can be born with Coc, Ace died as someone who was living to serve another man, yet he didn't lose his Coc, because his father had it and he was born with it. Any powerful and relevant character has potential to unlock it, if Oda wishes for it to be.