I hope they have a safe, uneventful trip. That being said, Geez, that sucks.
The last time I flew through Chicago, the weather was like it is tonight.
We ended up staying overnight in a hotel, but they won't give you your bags overnight, so you end up sleeping in your clothes anyway.
I did however have the only and best meatloaf sandwich I have ever had the pleasure of coming across!
That's because you've never had one of MY meatloaf sandwiches! LOL!!!
Just reminded me I need to re-assemble my mini toiletries kit and start carrying it again. Even a straight-through flight is no guarantee, as I discovered on a flight from Minneapolis to Seattle... where I wound up staying overnight in a hotel in Billings because one of the plane's engines failed.
I usually also have a shirt ("boxed"), change of underwear and socks in my backpack, just in case. And in case it's worse than that, the mini-kit has a couple packets of Woolite...