AA 3264 then UA 3876 at O'Hare
Dallas-Fort Worth → Chicago → Miami
Timetable, Chicago time
18:35AA 3264 from Dallas-Fort Worth at the gate
07:00UA 3876 to Miami leaves the gate
12 h 25 apart on the timetable, overnight
UA 3876 leaves 12 h 25 after AA 3264 arrives on the timetable: more than half a day, so not a connection we count.