What is Charlie Swan's nickname for Bella in 'Twilight'?

"Bells" is Charlie Swan's nickname for his daughter Bella in "Twilight."

Bella's name is actually Isabella. But she dislikes the name and prefers to shorten it to Bella. Charlie undoubtedly likes Bella's real first name, because he calls her that behind her back. To Bella's face, though, he has his own nickname of "Bells."