AA 4991 then UA 3876 at O'Hare
Kalamazoo → Chicago → Miami
Timetable, Chicago time
06:14AA 4991 from Kalamazoo at the gate
21:00UA 3876 to Miami leaves the gate
14 h 46 apart on the timetable
UA 3876 leaves 14 h 46 after AA 4991 arrives on the timetable: more than half a day, so not a connection we count.