Ear Worm: "Dancing in the Moonlight" from The Next Steps, a.k.a. "Slumber Party Song." You can watch the official music video from the Angelina YouTube feed here.
Nightmare Fuel: In "Angelina's Baby Sister", Angelina's new sister Polly becomes rattled when a prize Angelina was showing her falls and breaks; she then rolls herself off the bed; thankfully their mother caught her just in time.
Playing Against Type: An in-universe example in the 2002 episode "The Show Must Go On" - in a special Christmas production of Cinderella, the usually sweet Angelina is cast as the Wicked Stepmother (or "Stepmouse" as called on the show) while Priscilla Pinkpaws gets cast as Cinderella.