AA 3815 then AA 1353 at O'Hare
Hartford → Chicago → Las Vegas
Timetable, Chicago time
20:15AA 3815 from Hartford at the gate
16:59AA 1353 to Las Vegas leaves the gate
20 h 44 apart on the timetable, overnight
AA 1353 leaves 20 h 44 after AA 3815 arrives on the timetable: more than half a day, so not a connection we count.