UA 3988 then AA 5229 at Charlotte
Houston → Charlotte → Harrisburg
Timetable, Charlotte time
10:49UA 3988 from Houston at the gate
08:30AA 5229 to Harrisburg leaves the gate
21 h 41 apart on the timetable, overnight
AA 5229 leaves 21 h 41 after UA 3988 arrives on the timetable: more than half a day, so not a connection we count.