AA 9866 then AA 1898 at O'Hare
Marquette → Chicago → Jackson
Timetable, Chicago time
10:30AA 9866 from Marquette at the gate
09:58AA 1898 to Jackson leaves the gate
23 h 28 apart on the timetable, overnight
AA 1898 leaves 23 h 28 after AA 9866 arrives on the timetable: more than half a day, so not a connection we count.