There's Probably A Random Line From An Official Fnaf Coloring Book That Derails The Whole Thing - Tumblr Posts

I really wonder if they're setting it up so that Michael is Henry's son instead of William's. Obviously we see William pause when he reads Michael's full name, which was to make us think there'd be the reveal later in the movie that he's his father, but this didn't happen, so why did William pause? It also adds reason as to why William would go after Garrett, the implication has always been that William was very careful about who he targeted, why take a random kid from a random campsite? If Garrett is Henry's kid as well, it's an act of revenge. (This also leads to a possible set up of Garrett possessing the Puppet.) If I remember correctly all we get as to what happened to Mike's dad is that he left because he couldn't handle his wife's death.

(Side note, I know it could be interpreted as Mike of the movie being Mike Schmidt and not related to the Aftons at all, if you think that Schmidt wasn't an alias used by Michael Afton, and that the pause could have been because William knew that he might have killed Mike's younger brother based on last name and Garrett was just a random kid he targeted. But it's JUST A THEOR-)