Britney Spears and Jason Trawick partied into the early morning hours as they celebrated his 40th birthday and their engagement in Las Vegas.
Whether walking through Sugar Factory's retail shop, sitting side-by-side over dinner with friends at Sugar Factory American Brasserie or in their private section at Chateau Nightclub & Gardens, Britney and Jason were hand-in-hand and all smiles.
They were joined by two dozen friends and family members -- and a bodyguard or two -- for their dinner that included Brasserie's salmon and array of pizza, including the popular chocolate pizza and a decadent chocolate fountain dessert.
As a special birthday treat for her beau, Spears walked with Trawick through Sugar Factory's retail store after dinner, picking out sweet treats for each other and goodies for her sons, Preston and Jayden.
After dinner, it was upstairs to Chateau Nightclub, where thousands of fans cheered and shouted congratulations when they entered the club.
That's when the pop princess presented her new fiancé with a two-tier black and white birthday cake with "Happy Birthday Jason" displayed across the red velvet cake, Trawick's favorite.
The newly engaged couple danced up a storm, an eyewitness tells us.
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