AA 9909 then UA 5869 at O'Hare
Waterloo → Chicago → Sioux Falls
Timetable, Chicago time
17:10AA 9909 from Waterloo at the gate
16:00UA 5869 to Sioux Falls leaves the gate
22 h 50 apart on the timetable, overnight
UA 5869 leaves 22 h 50 after AA 9909 arrives on the timetable: more than half a day, so not a connection we count.