New parents Nicole Richie and Joel Madden head to her manager/talent agent Benny Medina’s house to celebrate his 40th birthday in Los Angeles on Friday.

Looks like Nicole is already back in shape, showing off her post-pregnancy body in a black hip-hugging dress.

Grandfather Lionel Richie, 58, was also seen at the party with his girlfriend.

Earlier in the day, Joel, 28, and Nicole, 26, were spotted stocking up on nursing supplies at The Pump Station earlier in the day.

Daughter Harlow Madden turned two-weeks-old yesterday.
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