Does your 3 or 4-year-old have a temper? How do you respond to outbursts? I generally try to be as neutral as possible, so as not to respond to anger with anger. But I'm not sure that they are time-out-worthy material, unless the involve throwing something (which they sometimes do!) or hitting little brother (ditto...). I am wondering how much of it is DD's nature, since she has always been super spirited and independent, and how much is just the age.
On a related note, which was easier for you, 3 or 4? People keep telling me 4 is difficult and emotional, but I am thinking DD is going through that now, since her communication skills have always been a little ahead of her other development.