A My little Pony next Generation thing.
CADENCE: "Ahahahahah! Ah, it seems you're not familiar with the royal lifestyle, are you, buck-o?"
It would make so much sense that Celestia asked Cadance herself to foalsit her since she would not have much time to take care with her ( ruling kingdom and such ), rather than Cadance showing up from nowhere to foalsit random unicorn filly.
Instead we must try to rationalize, for instance, why Noteworthy randomly transforms into a cyclops. Maybe he's an extraterrestrial pony, and his earth pony disguise rubbed off for a second?
Shining Armour is like 'wait...what?"
hehe, I was laughing at the oatslices and the "still got it!"