UA 3903 then UA 4013 at Houston
Newark → Houston → Harlingen
Timetable, Houston time
09:05UA 3903 from Newark at the gate
21:30UA 4013 to Harlingen leaves the gate
12 h 25 apart on the timetable
UA 4013 leaves 12 h 25 after UA 3903 arrives on the timetable: more than half a day, so not a connection we count.