AA 9908 then UA 4382 at O'Hare
Milwaukee → Chicago → Buffalo
Timetable, Chicago time
13:50AA 9908 from Milwaukee at the gate
10:30UA 4382 to Buffalo leaves the gate
20 h 40 apart on the timetable, overnight
UA 4382 leaves 20 h 40 after AA 9908 arrives on the timetable: more than half a day, so not a connection we count.