AA 4960 then UA 3907 at O'Hare
South Bend → Chicago → Washington
Timetable, Chicago time
14:40AA 4960 from South Bend at the gate
12:00UA 3907 to Washington leaves the gate
21 h 20 apart on the timetable, overnight
UA 3907 leaves 21 h 20 after AA 4960 arrives on the timetable: more than half a day, so not a connection we count.