UA 3908 then AA 4498 at O'Hare
Fort Myers → Chicago → Harrisburg
Timetable, Chicago time
14:19UA 3908 from Fort Myers at the gate
11:45AA 4498 to Harrisburg leaves the gate
21 h 26 apart on the timetable, overnight
AA 4498 leaves 21 h 26 after UA 3908 arrives on the timetable: more than half a day, so not a connection we count.