AA 547 then UA 4645 at O'Hare
Boston → Chicago → Fort Wayne
Timetable, Chicago time
15:29AA 547 from Boston at the gate
11:25UA 4645 to Fort Wayne leaves the gate
19 h 56 apart on the timetable, overnight
UA 4645 leaves 19 h 56 after AA 547 arrives on the timetable: more than half a day, so not a connection we count.