AA 3726 then UA 4550 at O'Hare
Dayton → Chicago → Columbia Regional
Timetable, Chicago time
20:14AA 3726 from Dayton at the gate
19:45UA 4550 to Columbia Regional leaves the gate
23 h 31 apart on the timetable, overnight
UA 4550 leaves 23 h 31 after AA 3726 arrives on the timetable: more than half a day, so not a connection we count.