Jessica Simpson Shows Off Weight Loss: I'm 'Too Proud To Sit Down!'

Just months after giving birth to her second child in two years, Jessica Simpson is looking more slim and svelte than ever.

The 33-year-old mom showed off her sexy frame while shooting a commercial on Friday.

“Too proud to sit down!! Behind the scenes of my new commercial,” Jessica captioned a photo on Instagram, where she is seen sporting a fitted, sleeveless black dress, with her blond hair down in loose waves. “Thanks @weightwatchers.”

PHOTOS: Stars Who’ve Slimmed Down After Giving Birth

In December, the singer/fashion mogul revealed she had reached her pre-pregnancy size.

“With both kids I’m running up and down my stairs a million times,” she told USA Today at the time, of how she shed the pounds.

Jessica and fiance Eric Johnson welcomed daughter Maxwell Drew in May 2012, and son Ace Knute in late June 2013.

-- Erin O’Sullivan

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