Little Hank was a demon that disguised himself as a baby in a plot to cause trouble for the Ghostbusters.
When Ray was watching after Hank, he gave him a teddy bear. Hank then turned the bear into a monster and made it chase Ray. When Janine saw what happened, she thought Ray was trying to leave Hank alone. Winston then tried to feed Hank, but Hank used the bottle to inflate Winston into a balloon. When Egon was in charge of Hank, he was going to give him a bath, but was then pushed into the bath and having to face a monster. After all of this, Janine decides that none of the Ghostbusters were trustworthy enough to take care of Hank, so she watches after him herself. Things get bad when Janine ends up imprisoned in Hank's crib and then realizes that Hank is actually a childlike demon. Fortunately, the Ghostbusters then came to trap Hank and put him into the Containment Unit. Despite all of the trouble he caused, Janine felt a bit sorry for Hank.