ET 574 then UA 5201 at O'Hare
Rome → Chicago → Milwaukee
Timetable, Chicago time
07:40ET 574 from Rome at the gate
20:00UA 5201 to Milwaukee leaves the gate
12 h 20 apart on the timetable
UA 5201 leaves 12 h 20 after ET 574 arrives on the timetable: more than half a day, so not a connection we count.