AA 4504 then UA 2189 at O'Hare
South Bend → Chicago → New York LaGuardia
Timetable, Chicago time
18:35AA 4504 from South Bend at the gate
13:00UA 2189 to New York LaGuardia leaves the gate
18 h 25 apart on the timetable, overnight
UA 2189 leaves 18 h 25 after AA 4504 arrives on the timetable: more than half a day, so not a connection we count.