AA 9950 then UA 535 at O'Hare
Philadelphia → Chicago → Houston
Timetable, Chicago time
13:49AA 9950 from Philadelphia at the gate
09:21UA 535 to Houston leaves the gate
19 h 32 apart on the timetable, overnight
UA 535 leaves 19 h 32 after AA 9950 arrives on the timetable: more than half a day, so not a connection we count.