OO 9909 then UA 752 at O'Hare
Waterloo → Chicago → Washington National
Timetable, Chicago time
16:47OO 9909 from Waterloo at the gate
12:29UA 752 to Washington National leaves the gate
19 h 42 apart on the timetable, overnight
UA 752 leaves 19 h 42 after OO 9909 arrives on the timetable: more than half a day, so not a connection we count.