Blair and 5-month-old son Arthur laugh it up in Beverly Hills. Plus: Russell Brand, Rihanna, Katy Perry and more

Credit: Jonathan Ernst/Reuters/Landov

Updated: Tuesday Jan 17, 2012 | 05:00 PM EST

FAMILY TIME

President Obama gets wife Michelle and eldest daughter Malia's support while greeting volunteers during a day of service to honor Martin Luther King Jr. in Washington D.C., on Monday.