AA 9782 then UA 3910 at O'Hare
Boston → Chicago → Chicago
Timetable, Chicago time
13:14AA 9782 from Boston at the gate
05:30UA 3910 to Chicago leaves the gate
16 h 16 apart on the timetable, overnight
UA 3910 leaves 16 h 16 after AA 9782 arrives on the timetable: more than half a day, so not a connection we count.