So you know how in Fnaf World he player is setting up the clues that are used in the Fnaf 3 mini games to get the happiest day ending?

It’s told in Fnaf world that “Everything that happens out there, has an effect here”, which is why to get the happiest day ending and free the main five animatronics’ souls in the spirit realm there needed to be some sort of input from the real world. That’s why to activate the second parts of those mini games the Fnaf 3 player character (basically confirmed canonically as Michael Afton) had to do something like insert a code in the wall keypad or do the arcade game.

Assuming that the Fnaf 4 Crying Child (also called Evan/Chris Afton) is the player in Fnaf World (see: the Universe End ending + head explosion) that’d mean that CC was sending his older brother clues to do what he couldn’t do in the real world to free those kids’ souls. If CC didn’t have faith that Mike would go out of his way to help free kids’ souls, and instead just walked away or actively sabotaged the effort like Mike would have done when he was a teenager, then I don’t think CC would have even bothered sending those clues, it would’ve been a waste of time and clocks. Maybe it was something about the persistence Mike had shown in uncovering his father’s crimes, tracking down ol peepaw Afton to Fazbear Frights, and having tried to burn the Fnaf 1 animatronics to free the souls that convinced CC enough to trust him with this, and low and behold Michael did pull through there, letting CC finish the job and deliver the cake in the spirit world.

I interpret this as the point where CC sort of, halfway reconciled with his brother who killed him by offering Michael a chance to help (likely not fully from how CC did it in the most cryptic way possible. Like imagine seeing Mike struggle to interpret those clues the people in the fandom were in the days following Fnaf 3’s release. CC definitely did that on purpose) and also where Michael made a biiigg step in his character arch and taking it that chance and help the kids literally without any benefit to him whatsoever. By now Michael has become a very changed man, and this is where that progress is really recognized.

On another note, do you remember CC’s foxy plush in Fnaf 4?

Well…

I think we found that Foxy’s head in Fnaf World.