I am sorry to hear that there is a medical necessity that brings you to Chicago and not better reasons. If you have already applied to Ronald McDonald House, which I know is wonderful for families in times like these, have you had the assistance of a hospital Social Worker in applying there? If so, I should think that the Social Worker might also likely be able to assist you with finding alternative accommodations should you not get into Ronald's for some reason. Indeed many patients are in similar circumstances such as yours and with medical matters, costs always tend to be an issue with any family like yours. Chicago city transit is fairly easy to use and the city is not too hard to get around. There are also some suburban commuter lines just outside the city, also easy to use should it be less expensive to stay slightly outside the city. And while I am sure we can help you find reasonable accommodations but I think you should get in touch with the hospital's Social Workers first to see how they can best assist you.
I have very good friends that must travel to Boston for help with their son's cardiac condition and while lately it's just been brief visits for status checks, there were times the entire family had to get quarters to live in while their little boy underwent surgery and treatment. They've used a hotel at times in outer parts of the city but they always make the long trip with their car so they have that to get around with. I know at times they have had to rely on Social Worker's guidance, especially when the boy's procedures began up in Boston. They are an essential part of the team that will be helping you and your daughter get through these challenging times. Utilize them as valuable resources for your needs there; I believe they are best suited to the job. If you still need us, we're here....
Keep us posted as to how things are going with planning and what we can do to help. I am sure I speak for us all here at Family Vacation Critic that we wish the very best of luck and best of health with regards to the treatments received in Chicago.
Yes, the weather should be moderate though Chicago can be a bit windy, especially at you get closer to the Lake. It might also feel a bit cooler if it rains, so do pack light jackets, perhaps a sweater each along with comfy clothes suitable to typical fall climate.