Simon Cowell's house was covered in toilet paper by Fifth Harmony.
The media mogul who turned 54 today (07.10.13) was given a birthday treat by the girlband - which includes Ally Brooke, Camila Cabello, Dinah Jane Hansen, Lauren Jauregui and Normani Kordei - who rose to fame on 'X Factor' USA last year.
"Happy 87th Birthday Simon! Love, Fifth Harmony."
According to gossip website TMZ.com the five-piece girl group made a mess around his home in Beverly Hills, Los Angeles, before leaving him with a banner which poked fun at his age, and read: "Happy 87th Birthday Simon! Love, Fifth Harmony."
Singer Demi Lovato - who is on the 'X Factor' USA panel alongside the Simon, Paulina Rubio and Kelly Rowland - was amused by the prank and tweeted: "HAHAHA YES @FIFTHHARMONY (sic)"
The 'Heart Attack' hitmaker will be accompanied by the girls on her 'Neon Lights' tour and is looking forward to getting up to some more mischief with them.
She added: "Oh this tour is gonna be fun HAHAHAHA @FifthHarmony @ddlovato (sic)"
Demi has her own treat lined up for Simon and although she didn't reveal what it was she too poked fun at his age, insisting she was going to give him a "Life Alert", which provide services that helps the elderly contact the emergency services.
She added: "Can't wait to give you your birthday present @SimonCowell!!", and attached am image which read "All Senior Citizens should have Life Alert."
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