UA 3913 then UA 4565 at Houston
Denver → Houston → Little Rock
Timetable, Houston time
21:22UA 3913 from Denver at the gate
12:12UA 4565 to Little Rock leaves the gate
14 h 50 apart on the timetable, overnight
UA 4565 leaves 14 h 50 after UA 3913 arrives on the timetable: more than half a day, so not a connection we count.