Simpson-Wentz and her 3-month-old son arrive at London's Heathrow Airport. Plus: Christina & Max, Britney Spears, Justin & Jessica and more

THEATRE BUFFS

Justin Timberlake, who offered an uncanny impersonation of John Mayer during Jimmy Fallon's Late Night premiere, keeps the laughs coming Tuesday, celebrating girlfriend Jessica Biel's 27th birthday at Will Ferrell's Broadway show, You're Welcome America. A Final Night With George W. Bush, in New York City.