AA 3872 then DL 2646 at O'Hare
Peoria → Chicago → Boston
Timetable, Chicago time
07:16AA 3872 from Peoria at the gate
19:45DL 2646 to Boston leaves the gate
12 h 29 apart on the timetable
DL 2646 leaves 12 h 29 after AA 3872 arrives on the timetable: more than half a day, so not a connection we count.