Our son gets frustrated at certain things, and mad when (for example, total hypothetical, it didn't happen yesterday) his sister knocks down a tower he's building and doesn't say sorry. We talk about the rules of getting mad (no hitting, walk away, tell a parent, etc.) and it's really helped. I read that four year old boys have a testosterone surge, and I guess this is part of it!

Does your LO have a temper?