AA 9950 then UA 441 at O'Hare
Philadelphia → Chicago → Dallas-Fort Worth
Timetable, Chicago time
13:49AA 9950 from Philadelphia at the gate
11:47UA 441 to Dallas-Fort Worth leaves the gate
21 h 58 apart on the timetable, overnight
UA 441 leaves 21 h 58 after AA 9950 arrives on the timetable: more than half a day, so not a connection we count.