Michael Wright / WENN 1 / 6
Michael Wright / WENN 1 / 6

Britney Spears rang in the big 2-8 on Wednesday by spending time with the people who mean the most to her: agent-boyfriend Jason Trawick, sons Sean Preston, 4, and Jayden James, 3, and the paparazzi, who serenaded the popster with a round of "Happy Birthday" as she and her squeeze got their shop on at Fred Segal in Los Angeles.

RELATED VIDEO: Britney gets cozy with her boys in Elle

Spears exited the boutique with several bags of retail booty, although if the contents resembled the outfit she had on (Buddy Holly glasses, jaunty two-toned fedora, and an inside-out long black sweater vest), she might want to check the store's return policy.

"Britney looked so happy," a spywitness tells People magazine. "She seemed very excited to spend her morning with Jason."

Later in the day, Spears and Trawick headed back to her Calabasas estate to celebrate with her tots, who pose with her on the cover of the January issue of Elle magazine.

Also joining in on the birthday fun were about twenty close friends and family, including her conservatorship-overseeing dad, Jamie, and some of her backup dancer pals, reports E! News.

Britney's big birthday surprise: a white convertible BMW with a bow around it (L.A. residents, consider yourselves warned). No wonder an insider describes her as being in "good spirits" at the alcohol-free party.

Alas, Brit didn't appear quite as cheery the night before, maintaining a poker face for swarming shutterbugs as she and Jason grabbed dinner, hit a spa, swung by the Chateau Marmont and checked into the Mondrian Hotel.

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Perhaps she's just annoyed by persistent engagement chatter, including a recent report that she unsuccessfully popped the question to Trawick while on tour in Australia.

While the aisle-walk rumblings have been denied (a lot), the Chicago Sun-Times remains optimistic, claiming the couple is looking to get hitched "early next year."

If the nuptials happen (and we cannot stress how huge an "if" that is), it apparently won't be a shotgun wedding.

Despite Star's contention that Spears recently aced a home pregnancy test, an insider is quick to dismiss the stork talk.

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