AA 547 then UA 5618 at O'Hare
Boston → Chicago → Washington National
Timetable, Chicago time
15:29AA 547 from Boston at the gate
14:00UA 5618 to Washington National leaves the gate
22 h 31 apart on the timetable, overnight
UA 5618 leaves 22 h 31 after AA 547 arrives on the timetable: more than half a day, so not a connection we count.