AA 2154 then UA 5194 at O'Hare
Charleston (South Carolina) → Chicago → Sioux City
Timetable, Chicago time
09:00AA 2154 from Charleston (South Carolina) at the gate
00:00UA 5194 to Sioux City leaves the gate
15 h apart on the timetable, overnight
UA 5194 leaves 15 h after AA 2154 arrives on the timetable: more than half a day, so not a connection we count.