AA 642 then UA 247 at O'Hare
Dallas-Fort Worth → Chicago → Omaha
Timetable, Chicago time
13:10AA 642 from Dallas-Fort Worth at the gate
12:40UA 247 to Omaha leaves the gate
23 h 30 apart on the timetable, overnight
UA 247 leaves 23 h 30 after AA 642 arrives on the timetable: more than half a day, so not a connection we count.