AA 2448 then UA 5201 at O'Hare
Harrisburg → Chicago → Milwaukee
Timetable, Chicago time
07:21AA 2448 from Harrisburg at the gate
20:00UA 5201 to Milwaukee leaves the gate
12 h 39 apart on the timetable
UA 5201 leaves 12 h 39 after AA 2448 arrives on the timetable: more than half a day, so not a connection we count.