Well, this is it. The infamous chapter. The very chapter that means this story isn't G-rated. The chapter with not one, but two, "sensitive content" warnings (one at the beginning and one at the end of the last one). Still, it's a comedy, an MLP story, and the main characters are toddlers, so it can't be too bad, can it? There's only one way to find out...
After the events of the previous chapter, Pumpkin thanks Pound and they go back to bed. The next morning, the parents and Pinkie Pie are none the wiser, just stumped as to why the bathroom floor and plunger are wet. At breakfast, Mrs. Cake seems to have a knowing smile, then she reveals that Pinkie Pie is going to try a new potty training trick on the twins.
Pinkie Pie comes in and brings them to the bathroom for "the Pinkie Pie School of Potty Training". She then sits them on their potties, which have been turned to face the toilet, and then goes out and comes back dressed and acting like a stereotypical professor. This just confuses the twins.
Then, Pinkie Pie goes out, takes off her professor outfit, and goes back, then sits on the toilet to demonstrate using the bathroom so the twins can learn by example. Then, the twins think of a prank: they just sit there, then Pinkie comes back wearing a large diaper, and pulls it down to signify that she's not using diapers but rather the toilet instead.
This backfires big time: the twins say that because she's wearing a diaper, she's now "one of them" and they don't need to listen to her. She is not pleased, but they keep teasing her and pretending she's just a cranky baby.
Mrs. Cake becomes concerned that the twins and Pinkie haven't come back yet, so she goes upstairs to check and is shocked to find Pinkie Pie in a diaper looking displeased, the twins chanting, "One of us now, big sister", Pound giving her a bottle, and Pumpkin giving her a pacifier. When the shock has worn off, Mrs. Cake laughs, as does Mr. Cake when he sees Pinkie Pie.
Everyone apologises and Pinkie Pie goes back to normal, but unfortunately she has wet herself.
This chapter provides examples of
- Actually Pretty Funny: When the prank is over, Pinkie Pie admits that it was funny.
- Baby See, Baby Do: Pinkie Pie tries to invoke this trope by having the babies copy her using the bathroom, but it doesn't work.
- Batman Gambit: The twins play dumb so that Pinkie Pie would put a diaper on to demonstrate.
- Dramatic Irony: Mr. Cake is saying that he's sure everything's fine, but we know that the twins have roped Pinkie Pie into an awkward situation that she doesn't want.
- Goo Goo Getup: Pinkie Pie wears a diaper to demonstrate pulling a diaper down to use a potty. Incidentally, this is why the chapter is so infamous: some people have recently been finding the idea of adults in diapers skeevy because of the increase of Rule 34 applying to adult diapers. Thankfully, this is not a Rule 34 story; the diaper situation is played purely for comedy, but the warning is there because some people can't shake the association.
- Mundane Made Awesome: Pinkie Pie treats potty training like a subject that needs an entire school devoted to it.
- Nerd Glasses: Pinkie Pie wears glasses when being a professor.
- Potty Failure: Pinkie Pie wets herself, which is especially odd as she's perfectly healthy but apparently didn't know she needed to pee. They say that "the milk went through her", but it's not like milk is a diuretic or anything like that.
- Tempting Fate: Pinkie Pie says that she's certain the twins won't prank her as she's a prankster herself. She couldn't be further from the truth.
- Through a Face Full of Fur: Pinkie Pie blushes visibly red despite being a horse.
