Villa got the better of West Bromwich Albion 2-0 at home in the quarter-finals of the competition on Saturday.
Fabian Delph put Villa in the lead six minutes into the second half, and Scott Sinclair added the second and ended the game as a contest five minutes from full time.
The match at Villa Park sparked into life in the second half and both sides had a player sent off, but in the end it was the Villans who was celebrating.
Gardner, who joined Forest on loan from Villa in the January transfer window, was delighted to see Tim Sherwood’s team book their place in the semi-finals and made the following post on Twitter.
And villa are off to wembley!!!! Well done lads!!!— Gary Gardner (@22Gards) March 7, 2015
Forest also won on Saturday, as they defeated Middlesbrough 2-1 at the City Ground in the Championship.