AA 9866 then AA 4999 at O'Hare
Marquette → Chicago → Wichita
Timetable, Chicago time
10:30AA 9866 from Marquette at the gate
09:42AA 4999 to Wichita leaves the gate
23 h 12 apart on the timetable, overnight
AA 4999 leaves 23 h 12 after AA 9866 arrives on the timetable: more than half a day, so not a connection we count.