AA 9799 then UA 3907 at O'Hare
New York JFK → Chicago → Washington
Timetable, Chicago time
16:51AA 9799 from New York JFK at the gate
12:00UA 3907 to Washington leaves the gate
19 h 09 apart on the timetable, overnight
UA 3907 leaves 19 h 09 after AA 9799 arrives on the timetable: more than half a day, so not a connection we count.