AA 9950 then UA 5459 at O'Hare
Charlotte → Chicago → Milwaukee
Timetable, Chicago time
08:30AA 9950 from Charlotte at the gate
21:20UA 5459 to Milwaukee leaves the gate
12 h 50 apart on the timetable
UA 5459 leaves 12 h 50 after AA 9950 arrives on the timetable: more than half a day, so not a connection we count.