AA 9908 then UA 2638 at O'Hare
Milwaukee → Chicago → Houston
Timetable, Chicago time
13:50AA 9908 from Milwaukee at the gate
10:34UA 2638 to Houston leaves the gate
20 h 44 apart on the timetable, overnight
UA 2638 leaves 20 h 44 after AA 9908 arrives on the timetable: more than half a day, so not a connection we count.