UA 3874 then AA 4099 at O'Hare
Chicago → Chicago → Cincinnati Northern Kentucky
Timetable, Chicago time
01:21UA 3874 from Chicago at the gate
16:50AA 4099 to Cincinnati Northern Kentucky leaves the gate
15 h 29 apart on the timetable
AA 4099 leaves 15 h 29 after UA 3874 arrives on the timetable: more than half a day, so not a connection we count.