Caught in the Act!

03/09/2007 at 05:00 PM EST

• Denise Richards, sharing a day of mother-daughter bonding in Malibu. The actress – who had daughters Lola, 21 months, and Sam, 3, scooped up in her arms, one of her favorite holding patterns – frolicked with her girls at a local playground.

• Ashley Olsen, showing off her sexy black boots for pal Megan Mullally at the Chateau Marmont hotel in West Hollywood. Olsen arrived with a group of friends and proceeded to Mullally's table on the patio, where she put her foot up and rolled up her jeans as the former Will & Grace star squealed with delight.

• Jeremy Piven, shopping for magazines with a pal at a Borders bookstore in Hollywood. And what was Ari reading? The Entourage actor picked up Rolling Stone and Details.

Beverly Hills Hotel

• Diana Ross, checking out a pair of black leggings at West Hollywood boutique Maxfield. Perhaps the singer was searching for an on-camera outfit: The Supreme diva will appear on American Idol on March 13 as a mentor to the Top 12 contestants.

• Reese Witherspoon, playfully reenacting her famous Legally Blonde pose with a fellow diner's pet Chihuahua while lunching with a pal at the Polo Lounge in The Beverly Hills Hotel. Witherspoon, who ate a salad, greeted the pooch after she finished her meal.

• By LYCIA NAFF

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