UA 6080 then AA 3768 at O'Hare
Sioux City → Chicago → St Louis
Timetable, Chicago time
07:35UA 6080 from Sioux City at the gate
20:59AA 3768 to St Louis leaves the gate
13 h 24 apart on the timetable
AA 3768 leaves 13 h 24 after UA 6080 arrives on the timetable: more than half a day, so not a connection we count.