We live in St. Louis and can't go too far or spend too much this year on a vacation, but really need a break so we decided to take the Amtrack up to Chicago for 3 or 4 days. DH and I used to go up there once or twice a year before kids. We plan to spend time on "the beach" and definitely want to visit the aquarium and maybe the Field Museum. Is there anywhere else we should visit? Keep in mind we have a 2 and 1/2 year old and a 5 month old and won't have a car. Are there any festivals coming up that are family-friendly? Any cool little place you locals know about? We don't want super packed days, just want to have some ideas in mind before we get there. We need to give DH's boss a few weeks' notice but, other than that, it doesn't matter when we go. Oh, and any ideas for places to stay would be appreciated, too. I know that will be our biggest expense but would love to know about a good deal on a comfortable place. TIA.