We just got back from our vacation (staying with family in Michigan) and I must say that traveling with a baby is quite different than just 2 adults. I think we took more stuff for her than we did for ourselves - and her clothes are 1/6th of my clothes size! If you're a parent, you know what I'm talking about!
Although our daughter isn't old enough for "activities" in the car (other than gnawing on a teething ring), I'm tucking away this bit of advice for traveling with kids. Go check out iheartorganizing's post on "A Travel Bag Full of Magic." What a great idea, even for the quick trip to the doctor's!