OO 9909 then UA 5756 at O'Hare
Waterloo → Chicago → Detroit
Timetable, Chicago time
16:47OO 9909 from Waterloo at the gate
10:47UA 5756 to Detroit leaves the gate
18 h apart on the timetable, overnight
UA 5756 leaves 18 h after OO 9909 arrives on the timetable: more than half a day, so not a connection we count.