This is the best theory you will see in the history of FNaF's Fandom. Actually, because this has the most compelling evidence, it can be considered as a fact!
TOY CHICA HAS A CUPCAKE!!!
She holds it whenever she goes, and Chica has a cupcake too. It would be wise for her remake to have a cupcake.
See? Only 2 evidences, but, they are very compelling!
TOY FREDDY IS FAT!!!
He looks fat, and he has a short route. He doesn't want longer routes. And he IMMEDIATELY rests when he doesn't get you. He goes back to the stage. And he doesn't lunge at you, but he only shakes his head!
SCOTT CAWTHON CREATED FNAF 1, 2, AND 3!!!
There is "(c) Scott Cawthon" on the lower-right of the menu screen!