UA 1903 then AA 3039 at Houston
Guatemala City → Houston → Chicago
Timetable, Houston time
17:51UA 1903 from Guatemala City at the gate
17:23AA 3039 to Chicago leaves the gate
23 h 32 apart on the timetable, overnight
AA 3039 leaves 23 h 32 after UA 1903 arrives on the timetable: more than half a day, so not a connection we count.