AA 4523 then UA 4789 at O'Hare
Baltimore → Chicago → Fargo
Timetable, Chicago time
20:00AA 4523 from Baltimore at the gate
19:45UA 4789 to Fargo leaves the gate
23 h 45 apart on the timetable, overnight
UA 4789 leaves 23 h 45 after AA 4523 arrives on the timetable: more than half a day, so not a connection we count.