AA 1200 then UA 3872 at O'Hare
Washington National → Chicago → LCQ
Timetable, Chicago time
11:34AA 1200 from Washington National at the gate
00:31UA 3872 to LCQ leaves the gate
12 h 57 apart on the timetable, overnight
UA 3872 leaves 12 h 57 after AA 1200 arrives on the timetable: more than half a day, so not a connection we count.