AA 6331 then UA 5194 at O'Hare
Burlington (BTV) → Chicago → Sioux City
Timetable, Chicago time
08:59AA 6331 from Burlington (BTV) at the gate
00:00UA 5194 to Sioux City leaves the gate
15 h 01 apart on the timetable, overnight
UA 5194 leaves 15 h 01 after AA 6331 arrives on the timetable: more than half a day, so not a connection we count.