Hollywood's biggest stars let their hair down on Sunday night for the 2012 MTV Movie Award where Twilight and Hunger Games win big; Gwen Stefani and sons Zuma and Kingston attend the Elizabeth Glaser Pediatric AIDS Foundation's 23rd Annual "A Time For Heroes"; Victoria Beckham and Reese Witherspoon step out to Greystone Mansion in Beverly Hills on Sunday for some family fun, to benefit the One Voice Scholars; Spike TV hosts their 6th Annual Guy's Choice Awards where stars like Justin Timberlake, Emma Stone and Kobe Bryant all go home with well-deserved awards; Ashley Tisdale and Audrina Patridge hit the Colgate Optic White Beauty Bar at 901 Salon for some pre-MTV Movie Awards pampering; Paris and Nicky Hilton attend a private birthday party for Allison Melnick—it was another action-packed weekend of summertime fun here in L.A. and we've got all the details on what went down and who partied where in this edition of Last Night's Parties.

[Gwen Stefani via]

Lindsay Lohan Nicky Hilton Evan Ross Charlize Theron Justin Timberlake Brandon Davis Kristen Stewart MTV Leighton Meester Julianne Hough Reese Witherspoon The Black Keys tom arnold Kate Beckinsale Twilight Jennifer Aniston Sharon Stone Jessica Biel Victoria Beckham Daisy Fuentes Andy Samberg Elizabeth Glaser Pediatric AIDS Foundation Pete Wentz Audrina Patridge Ashley Tisdale Jessica Stroup Russell Brand Kristen Bell Channing Tatum Disney Maria Menounos Elizabeth Banks Kathy Hilton MTV Movie Awards Taylor Lautner Matthew McConaughey Emma Watson Catt Sadler Stoli Mark Wahlberg Breckin Meyer Logan Lerman Gwen Stefani zuma rossdale kingston rossdale Jamie Chung Mila Kunis Spike TV Trevor Donovan Steven Tyler Joseph-Gordon Levitt TOMS Shoes Johnny Depp Shailene Woodley Kendra Wilkinson Dax Shepard Greg Kinnear Adam Sandler Jodie Foster Emma Stone Allison Melnick Bryan Greenberg Charlie Sheen Lori Loughlin Nikki Reed Jim Belushi Malin Akerman W Hollywood Christopher Nolan Kylie Jenner Christian Bale Josh Hutcherson Fernanda Romero Fake Bake Ed O'Neill Dan Auerbach Patrick Carney Amber Lancaster Janelle Monae Christina Milian Andrew Garfield Ariel Winter Joe Manganiello Carmen Electra Taylor Armstrong Foxy Shazam jean-claude van damme Jennifer Lawrence Cassie Scerbo Drake Bell Wiz Khalifa Chris Hemsworth Kate Linder Camilla Luddington Crystal Reed Michael Fassbender Bob Iger Jeff Garlin Paris Hilton