AS 583 then DL 438 at Seattle
Chicago O'Hare → Seattle → Boston
Timetable, Seattle time
12:14AS 583 from Chicago O'Hare at the gate
11:45DL 438 to Boston leaves the gate
23 h 31 apart on the timetable, overnight
DL 438 leaves 23 h 31 after AS 583 arrives on the timetable: more than half a day, so not a connection we count.