My apologies if there is a thread somewhere already on this topic, but I couldn't find a recent one, and I've been wondering about it lately, so I thought I would post myself on this issue. Although ...
If they had legos, I mean "stacking bricks", there could be the chance of a hilarious animation and moodlet to go with it: Stepping On Them. I can just see my parent Sims doing the Stepped On a Brick dance!