UA 3908 then AA 6255 at O'Hare
Fort Myers → Chicago → Sioux Falls
Timetable, Chicago time
14:19UA 3908 from Fort Myers at the gate
12:56AA 6255 to Sioux Falls leaves the gate
22 h 37 apart on the timetable, overnight
AA 6255 leaves 22 h 37 after UA 3908 arrives on the timetable: more than half a day, so not a connection we count.