UA 5859 then AA 3484 at O'Hare
Flint → Chicago → St Louis
Timetable, Chicago time
09:43UA 5859 from Flint at the gate
09:30AA 3484 to St Louis leaves the gate
23 h 47 apart on the timetable, overnight
AA 3484 leaves 23 h 47 after UA 5859 arrives on the timetable: more than half a day, so not a connection we count.