B6 8378 then AA 888 at Boston
Las Vegas → Boston → Chicago O'Hare
Timetable, Boston time
09:19B6 8378 from Las Vegas at the gate
16:47AA 888 to Chicago O'Hare leaves the gate
7 h 28 apart on the timetable
Boston’s board gives an arrival time for only about 58% of its flights, so many days show no gate time.
The last days
B6 8378 and AA 888 weren’t both flown 15 min to 12 h apart in the last 21 days.
Statistics from past flights, not live flight information. Always check times and your connection with your airline, and don’t base travel or booking decisions on these numbers.