The title is based on The Joker's quote "Why so serious" from The Dark Knight.
Pat using Mark's research in order to treat Dion's ailment may be a nod to Mighty Med (2013) in which comicbooks provide information about superheroes' bodies which helps diagnose and treat their conditions.
Despite referencing vomit in the title, there isn't any in the episode.
Dion's aunt Kat discovers about his powers in this episode.