AA 2258 then UA 4772 at O'Hare
Las Vegas → Chicago → Columbia Regional
Timetable, Chicago time
12:52AA 2258 from Las Vegas at the gate
12:45UA 4772 to Columbia Regional leaves the gate
23 h 53 apart on the timetable, overnight
UA 4772 leaves 23 h 53 after AA 2258 arrives on the timetable: more than half a day, so not a connection we count.