BA 777 then AA 9600 at Heathrow
Stockholm → London → Chicago
Timetable, London time
13:25BA 777 from Stockholm at the gate
13:00AA 9600 to Chicago leaves the gate
23 h 35 apart on the timetable, overnight
AA 9600 leaves 23 h 35 after BA 777 arrives on the timetable: more than half a day, so not a connection we count.