UA 3501 then AA 4991 at O'Hare
Kansas City → Chicago → Nashville
Timetable, Chicago time
17:05UA 3501 from Kansas City at the gate
08:50AA 4991 to Nashville leaves the gate
15 h 45 apart on the timetable, overnight
AA 4991 leaves 15 h 45 after UA 3501 arrives on the timetable: more than half a day, so not a connection we count.