Then you're going to LIVE for this video!!!
She's gone undercover -- and she OWNS it!
Ch-ch-check out the video for Birthday here (above)!
We knew there had to be some truth to the rumors!
"I haven't asked him, but when I was at X Factor [USA, earlier this week] Alberto from security said Niall's girlfriend Barbara was here."
That sounds like they’re an item to us! Why else would she be there to cheer him on?!
Just hurry up and confirm it already!
[Image via WENN.]