Marinette and Chloe used to be friends as children. They were close, but they didn't know how close. After Chloe's mom died, Chloe became a brat. By hurting people, she thought that she'd get over the hurt. But, she didn't. She hurt everyone. Including her best friend, Marinette.

They used to have nicknames for each other. Marinette was "Mari-bear" and Chloe was "Chloe-bee". They were friends before Chloe even met Adrien. Ever since they were babies. But, kids grow up and so did they.