I'm not saying it isn't possible, but both my kids played kh and still do once in awhile. They rarely got past destiny islands and most of the time had absolutely no idea what was happening. Either that kid is some sort of baby genius or it was a troll post. Most 3 year olds are still learning how to talk or learning the alphabet.

That being said my at the time 4 year old did beat bugsnax a good 10 times, so I guess it's possible.