Class 1a went on a trip recently, to get off from hero studies and work, and izuku managed to get hit by a quirk that turned him 2.

It wasnt quite surprising since Izuku pretty much manages to put himself into trouble a lot, but it was still sorts surprising since he was turned into a toddler.

Since they were still at the trip, and would be for a month or two, theyve decided to take care of him until Aizawa gets out of the hospital and they try to turn him back.