OO 9909 then OO 391 at O'Hare
Waterloo → Chicago → Detroit
Timetable, Chicago time
16:47OO 9909 from Waterloo at the gate
14:30OO 391 to Detroit leaves the gatealso UA 391
21 h 43 apart on the timetable, overnight
OO 391 leaves 21 h 43 after OO 9909 arrives on the timetable: more than half a day, so not a connection we count.