AA 986 then DL 1556 at O'Hare
Baltimore → Chicago → Los Angeles
Timetable, Chicago time
08:50AA 986 from Baltimore at the gate
07:45DL 1556 to Los Angeles leaves the gate
22 h 55 apart on the timetable, overnight
DL 1556 leaves 22 h 55 after AA 986 arrives on the timetable: more than half a day, so not a connection we count.