AA 4272 then UA 5201 at O'Hare
Allentown → Chicago → Milwaukee
Timetable, Chicago time
07:15AA 4272 from Allentown at the gate
20:00UA 5201 to Milwaukee leaves the gate
12 h 45 apart on the timetable
UA 5201 leaves 12 h 45 after AA 4272 arrives on the timetable: more than half a day, so not a connection we count.