Reese Witherspoon Shows Off Slim Post-Baby Body in Lacy Black Dress

Reese Witherspoon on December 6, 2012 in Beverly Hills, California.  Jason LaVeris/FilmMagic

Reese Witherspoon looked radiant in her second red carpet appearance since welcoming son Tennessee James Sept. 27.

At the Children's Defense Fund-California's 22nd Annual "Beat the Odds" Awards in Beverly Hills Dec. 6, the new mom, 37, showed off her svelte post-baby body in an Elie Saab black, sleeveless cocktail dress that featured sheer lace and pleat details. Witherspoon stood tall in black Christian Louboutin heels.

The Devil's Knot star was accompanied by her 13-year-old daughter, Ava Phillippe, and 64-year-old mother, Betty Witherspoon. "Ava was perfectly behaved and looked very serious and intent while listening to the stories of children who had dealt with misfortune," an attendee tells Us Weekly.

Witherspoon recently shared a meal with sitcom star Mindy Kaling at Tavern Restaurant in L.A.'s Brentwood neighborhood. Though Kaling, 33, won't say if the lunch date was a business meeting, she did tell E! News that she would love if the Academy Award winner guest starred on FOX's The Mindy Project.

"Because she's so sweet and so articulate and well raised, to me it would be really fun to have her play somebody out of control," the Is Everybody Hanging Out Without Me? author said. "That would be really fun for me."

Witherspoon, meanwhile, has been spending her days looking after her 10-week old baby boy — her first with husband Jim Toth. (She is also mom to Deacon, 8, with ex-husband Ryan Phillippe, 38.)

"He's been there for Reese every step of the way," an insider told Us of talent agent Toth, 42. "He's a little nervous, but very excited his son is finally here!"

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