UA 3532 then AA 4912 at O'Hare
Knoxville → Chicago → Grand Rapids
Timetable, Chicago time
18:43UA 3532 from Knoxville at the gate
13:10AA 4912 to Grand Rapids leaves the gate
18 h 27 apart on the timetable, overnight
AA 4912 leaves 18 h 27 after UA 3532 arrives on the timetable: more than half a day, so not a connection we count.