UA 4757 then AA 3484 at O'Hare
Appleton → Chicago → St Louis
Timetable, Chicago time
11:12UA 4757 from Appleton at the gate
09:30AA 3484 to St Louis leaves the gate
22 h 18 apart on the timetable, overnight
AA 3484 leaves 22 h 18 after UA 4757 arrives on the timetable: more than half a day, so not a connection we count.