Waterfall Glen, located in the southern burbs of Chicago, is definitely nature's hidden gem. It is a bit of a walk to get to it (about ten minutes or so down a hill), but one hundred percent worth it. While you do have to pay close attention to the kids because safety first, everyone always loves splashing about and dipping their toes in the water. Highly recommend bringing a towel and maybe even extra shoes for your little.
Another thing to keep in mind is bug spray is a MUST. You have to be careful because sometimes it shows up on darker clothing leaving little white dots, so do a test run before your photo day. However, the mosquitoes are relentless. Especially in the summer heat. Lastly, parking is limited so many times you have to park along the street. There is not clear labeled sign leading you to the waterfall, so be sure you are well informed before hand.