AA 2612 then UA 4550 at O'Hare
Houston → Chicago → Columbia Regional
Timetable, Chicago time
20:22AA 2612 from Houston at the gate
19:45UA 4550 to Columbia Regional leaves the gate
23 h 23 apart on the timetable, overnight
UA 4550 leaves 23 h 23 after AA 2612 arrives on the timetable: more than half a day, so not a connection we count.