AA 642 then UA 224 at O'Hare
Dallas-Fort Worth → Chicago → Bozeman
Timetable, Chicago time
13:10AA 642 from Dallas-Fort Worth at the gate
09:07UA 224 to Bozeman leaves the gate
19 h 57 apart on the timetable, overnight
UA 224 leaves 19 h 57 after AA 642 arrives on the timetable: more than half a day, so not a connection we count.