During the circus montage at the beginning of the film, there is a brief shot of a hand balancing and twirling a set of four crystal balls. This art is called Contact Juggling, created by performance artist Michael Moschen and originally debuted in the Jim Henson film Labyrinth (1986), which in part inspired this film.
Valentine: My mum always said: "It's a dog-eat-dog world, son. You get them before they get you. Eat your greens. Stop embarrassing me in front of the neighbors. Maybe it would best if you leave home and never come back!"