AA 4504 then UA 5375 at O'Hare
South Bend → Chicago → Grand Rapids
Timetable, Chicago time
18:35AA 4504 from South Bend at the gate
15:48UA 5375 to Grand Rapids leaves the gate
21 h 13 apart on the timetable, overnight
UA 5375 leaves 21 h 13 after AA 4504 arrives on the timetable: more than half a day, so not a connection we count.