The imported candy can have a different effect each time you use if Sweetie. It's kind of unsafe to use unless you're really daring. I'll list in a spoiler button some of the things that has happened when I've used it.
Click to reveal..
One peep got three years younger; Some acted like they had been scolded; Some acted like they had been praised; One got older when it was given to them; Sometimes it seems to have on effect at all.


I'm sure there are other effects it could have, but I didn't want to take the chance on trying it anymore and haven't in a long time.