FA Cup: Scott McTominay headed home the only goal after just eight minutes, but Villa were left to rue a host of missed chances and a controversial VAR review that ruled out an equaliser from Danny Ings in the second half.
With nine minutes remaining, substitute Danny Ings fired home after Southampton were awarded a spot-kick, with Brighton players claiming the foul took place outside the area.
Dominic Calvert-Lewin opened the scoring at Wembley with his 10th goal this season after netting nine times in six games for Everton.
Daniel Sturridge, apparently has sustained a hamstring problem and is most likely to sideline him for a few weeks.