UA 3565 then AA 3484 at O'Hare
Indianapolis → Chicago → St Louis
Timetable, Chicago time
09:36UA 3565 from Indianapolis at the gate
09:30AA 3484 to St Louis leaves the gate
23 h 54 apart on the timetable, overnight
AA 3484 leaves 23 h 54 after UA 3565 arrives on the timetable: more than half a day, so not a connection we count.