The former Oasis star was cheered on by a number of guests as he broke into the catchy acoustic of 'Happy Birthday' at 6am yesterday (19.01.14) in celebration of the supermodel's milestone age.
Kate - who kicked off her celebrations with a posh lunch on Thursday (16.01.14) - reportedly spent £30,000 on entertainment for the big bash at her Cotswolds home on Saturday night (18.01.14).
Florence and the Machine, Mark Ronson, Soul II Soul and Massive Attack performed in yurts in the garden, while there were also tarot card readings, fire jugglers and face-painters on hand throughout the Glastonbury-themed party.
The blonde beauty reportedly paid out a hefty £80,000 on spirits and an endless supply of champagne to keep her guests entertainment.
Uma Thurman, Naomi Campbell and Stella Mccartney were just a few of her famous friends in attendance, but all mobile phones were to be handed in at the door to stop any drunken photos being uploaded to Twitter or Instagram.
A source told The Sun newspaper: ''Everyone knew it was going to be a wicked party, which it was.
''It was truly epic and isn't even over yet... ''
Meanwhile, Kate hired the dining room at a local pub last night (19.01.14) for her and the remaining guests who were still standing after a boozy four days of partying.