Star Tracks - Friday, December 21, 2007

Before skipping out on dance time at Millennium studio, Britney Spears drops by a Hollywood souvenir shop to pick up some items suited for a little one, though a source says she's still in shock over sister Jamie Lynn's pregnancy.

Eva Mendes gets cheeky while posing in front of her newly unveiled "I'd Rather Go Naked" PETA ad Thursday in Beverly Hills.

After rubbing elbows with Jack Nicholson on the West Coast, John Mayer was kicking up his feet with the paparazzi Thursday outside New York's Waverly Inn.

Shakira gets a lesson at a local Bangladesh primary school Wednesday while visiting the country on behalf of UNICEF.

Zac Efron lets his hair down Thursday as he continues work on the Santa Monica set of his movie Seventeen.

Before heading to Telluride for the holidays, Tom Cruise leaves the family at home for a dinner at Beverly Hills steakhouse Cut on Thursday.

Paris Hilton and her sometime boyfriend Alex Vaggo make sure they're color

coordinated for an evening out Thursday at Goa nightclub in Hollywood.

Brad Pitt, who plans on another seven to nine kids with partner Angelina Jolie, enjoys a 44th birthday ride through New Orleans on Tuesday with two of the couple's children, Maddox, 6, and Zahara, 2.

Take PEOPLE's Brad Pitt birthday pop quiz here!

Getting caught up in the holiday frenzy, mom-to-be Jennifer Lopez squeezes in some last-minute shopping at Barneys New York in Manhattan on Thursday.

While mom Gwen Stefani pushes the baby carriage, dad Gavin Rossdale totes his greatest triumph, 16-month-old son Kingston, during an outing at a London park on Thursday.

Continuing their Big Apple adventures, 2-year-old Violet Affleck points out a sight worth seeing to mom Jennifer Garner as the duo stroll through Manhattan's Upper West Side on Thursday.

It's a family affair! Giving the next generation a taste of the limelight, the Spice Girls bring out their little ones during their final hometown performance of the year at London's O2 Arena on Tuesday.

While her 16-year-old sister Jamie Lynn's pregnancy continues to generate headlines, Britney Spears puts on a happy face while driving around West Hollywood on Wednesday.

She's a woman of letters! Rumer Willis minds her p's and q's as she grabs a bite at Urth Caffé in West Hollywood on Wednesday.