Mike and Vanna's relationship. They joke around, get into arguments, and mess around with each other, but they're also there for each other no matter what.
Any time a human character finds the ghost of a loved one. Once the initial fear is worked out, the interactions after are sweet.
All of the animatronics protect and speak for the children haunting them. They also watch out for living children to try to prevent another tragedy.
The 1987 animatronics came after Jeremy Fitzgerald because they were trying to protect him. They failed, unfortunately, but not without effort.
In this universe, the reason Fredbear's Family Diner exists is because the owner lost her husband and was trying to honor him.
Mike trying to make sure Jamie Green had a good birthday.
Most of Puppet's interactions with Bonnie Wickes.
Bonnie considers Puppet to be her greatest creation.
Vanna is pretty bitter about her family, so the fact that she wants to get to know Will, and by that extent, Bonnie and Freddy Wickes, says a lot.
Freddy Wickes spent over two decades figuring out how to communicate through items in the building first, to be near his wife, and then to get the truth out.
All of the ghosts wait for Puppet to come back online just to give their thanks.