Watch: Britney Spears Sings “Happy Birthday” to L.A. Reid on X Factor

Proving nay-sayers that she’s entitled to her seat on the judges panel on X Factor USA, Britney Spears showed off her vocals on the latest episode of the show, which featured a surprise moment for L.A. Reid.

Above is the video.

It was L.A. Reid’s birthday, but he did not expect a surprise from his fellow judges, Britney, Demi and Louis Walsh who stood in for Simon Cowell at the auditions.

Britney and fiancé Jason Trawick came in with the cake, singing “Happy Birthday,” which obviously moved L.A. Reid beyond words.

Britney too was pretty nervous, judging by how her voice faltered at one point but this only made the moment all the sweeter.

Check it out.