|Series||The Grim Adventures of Billy & Mandy|
|Cartoon Network US Premiere||June 5, 2006|
|Paired with||Dad Day Afternoon|
Dad Day Afternoon
- Story by: Shaun Cashman
- Storyboard by: Alex Almaguer
- Directed by: Sue Perrotto
When Billy's mother realizes that Mandy has become an eternal houseguest, Mandy returns home. But her own parents can't deal with her and they hire a nanny bent in shaping her into a proper young girl.
At Billy's house, Gladys calls for Harold, Billy and Mandy to report to dinner, but refuses. Gladys' insane temper triggers and she wrecks her husband with a chainsaw, forcing the trio to report to dinner. She, however, excuses Mandy due to realizing that she is an eternal houseguest and constantly remarks as she is not part of the family. She returns home, with her parents terrified and are so scared of her. When she demands dinner, they had enough and decide to call a nanny. The nanny does everything she can to get Mandy's family to stand up for themselves, but Mandy is too ruthless and mean to stand up to. Grim decides to intervene by making Mandy's parents assertive, but even then, Mandy wins and even has her minions kill the nanny.
- The plot is a reference to the ABC TV show Supernanny. The title is a reference to Mary Poppins.
- Billy telling Mandy and the nanny to fight with laser swords could be a reference to the Star Wars movies.
- Mandy controls her parents by telling them what they want to do and making a hand motion which is a reference to the Jedi mind trick in the Star Wars movies.
- Mandy being in charge of her family could be a reference to The Twilight Zone episode "It's A Good Life", where a young boy controls his family with unnatural powers.
- In Sickly Sweet, Mandy couldn't pronounce the word "please" without it being clear. But in Scary Poppins, Mandy says "Okay, go suck a lemon, please" without any problems.
- (Response: She had to say it nicely. But in this episode, she said it to be rude.)