AA 9866 then AA 4132 at O'Hare
Marquette → Chicago → Huntsville
Timetable, Chicago time
10:30AA 9866 from Marquette at the gate
08:15AA 4132 to Huntsville leaves the gate
21 h 45 apart on the timetable, overnight
AA 4132 leaves 21 h 45 after AA 9866 arrives on the timetable: more than half a day, so not a connection we count.