Star Tracks: Monday, April 4, 2011

An unrecognizable Kate Walsh shows off her disco moves at a 42 Below Vodka-sponsored bash in celebration of her new unisex fragrance, Boyfriend, in L.A. on Saturday.

After spending family time with her brood, Angelina Jolie departs L.A. on Sunday for a goodwill mission, reportedly to the Middle East.

Mama-to-be Kate Hudson and her boys – son Ryder, 7, and beau Matt Bellamy – check out local goods while touring the Recoleta neighborhood in Buenos Aires, Argentina, on Saturday.

Miley Cyrus skips country's big night at the ACM Awards for a family meal – with dad Billy Ray, mom Tish and sisters Noah and Brandi – at the Cheesecake Factory in Sherman Oaks, Calif., on Sunday.

The Band Perry (from left, siblings Neil, Kimberly and Reid) happily show off their new hardware – for new vocal group of the year – at the Academy of Country Music Awardson Sunday at the MGM Grand Garden Arena.

Download free songs from The Band Perry and other ACM Awards newbies right here!

Room for one more? Ellen Pompeo and hubby Chris Ivery engage in a courtside cuddle Sunday as Jeremy Piven looks on during a Lakers-Nuggets home game.

Justin Bieber makes a commanding – and color-coordinated – display on stage at the O2 World Arena in Berlin, during the second stop on the teen star's My World tour Saturday night.

She got soaked! Heidi Klum is a model guest – and a good sport – at Saturday's Nickelodeon Kids' Choice Awards in L.A., where the supermodel presented Selena Gomez with best TV actress, and then got slimed!

Justin Timberlake focuses on what really matters – his fans! – while accepting the Big Help Award at Saturday's Kids' Choice Awards in L.A.

Willow Smith is flying high on the crowd's energy, making one dramatic (and high-flying) entrance at Saturday's Kids' Choice Awards, while performing her hit, "Whip My Hair."

It's almost ACM time! The guys of Rascal Flatts – Joe Don Rooney and Jay DeMarcus – get some love from their wives, Tiffany Fallon (far left) and Allison Alderson (far right), at PEOPLE Country's "Nashville in Vegas" bash at the Bank Nightclub on Saturday. The Academy of Country Music Awards airs on Sunday at 8 p.m.

Christina Aguilera is happy to play hands-on mom, picking up 3-year-old son Max from his Santa Monica, Calif., preschool on Friday.

She does work out! Though she has said she was born with the to model, Gisele Bündchen fits in a gym visit Friday in Studio City, Calif.

Joe Jonas embraces the single life and flaunts his buff arms while leaving an L.A. Starbucks in a bicep-baring tank on Friday.

Practice makes perfect! Country superstar Miranda Lambert takes her place behind the mic to rehearse for Sunday's Academy of Country Music Awards in Las Vegas on Friday.

Mama-to-be Pink – who recently said her pregnancy makes her clumsy – takes cover while strolling the beach in Malibu, Calif., with hubby Carey Hart (not pictured) Thursday.

He may not be touring with Britney Spears but Enrique Iglesias still commands the stage during his own performance Thursday at Palais Nikaia in Nice, France.

...And eating it too! Selena Gomez celebrates Radio Disney's 15th birthday on Friday by having a sweet treat with hosts Ernie D and Jake Whetter in Burbank, Calif.