Gleeson joins the cast as Patrick Winslow's stepfather Victor Doyle, while Smoove will voice the new character, Hackus, who is described as "naughty."
Gosnell will return to helm the second film. Producer Jordan Kerner and executive producer Ezra Swerdlow will also be back.
Production has begun on the Sony Pictures Animation sequel.
Original cast members such as Neil Patrick Harris, Jayma Mays, Sofia Vergara and Katy Perry are all returning for the sequel. No synopsis released yet.