CX 99 then UA 3376 at O'Hare
New York JFK → Chicago → St Louis
Timetable, Chicago time
17:00CX 99 from New York JFK at the gate
11:00UA 3376 to St Louis leaves the gate
18 h apart on the timetable, overnight
UA 3376 leaves 18 h after CX 99 arrives on the timetable: more than half a day, so not a connection we count.