UA 1901 then UA 3907 at Houston
Guatemala City → Houston → Washington
Timetable, Houston time
10:03UA 1901 from Guatemala City at the gate
07:00UA 3907 to Washington leaves the gate
20 h 57 apart on the timetable, overnight
UA 3907 leaves 20 h 57 after UA 1901 arrives on the timetable: more than half a day, so not a connection we count.