AA 6255 then UA 5940 at O'Hare
Sioux Falls → Chicago → Peoria
Timetable, Chicago time
17:29AA 6255 from Sioux Falls at the gate
16:40UA 5940 to Peoria leaves the gate
23 h 11 apart on the timetable, overnight
UA 5940 leaves 23 h 11 after AA 6255 arrives on the timetable: more than half a day, so not a connection we count.