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Eric Johnson is one lucky guy. Jessica Simpson is "too proud" about her slimmed down figure, and showed off her stunning transformation once again via Instagram on Friday.

PHOTOS: Jessica's body evolution

"Too proud to sit down!! Behind the scenes of my new commercial. Thanks @weightwatchers," Simpson, 33 wrote. The brand spokeswoman shared a black and white behind-the-scenes picture of herself gearing up to film her latest ad. Johnson's beautiful fiancee wore a tight-fitted ensemble for the shoot, and kept her blonde locks down in waves.

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Simpson has been working hard to get back in shape since giving birth to her son Ace last June. (She and the former NFL player, 34, welcomed their baby boy just 14 months after the birth of their daughter Maxwell, 20 months.) And the work has clearly paid off. On Jan. 8, Simpson shared her most impressive weight loss photo yet during an appearance on LIVE with Kelly and Michael.

"LIVE with Kelly and Michael! Thx y'all! Had a blast," she wrote at the time, with a backstage photo of herself wearing a body-hugging floral knee-length dress.

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Besides having a future wedding to get ready for, Simpson also addressed another reason she's been inspired to drop the weight -- her baby girl Maxwell. "I want her to look up to me and be like me," the former Fashion Star mentor said on Good Morning America on Jan. 7. "I don't want to give her any false perception of what is real and what's important. It is important to really know yourself and love yourself."

She added: "As a mom, I just have this confidence. I just feel so proud of what I've done and what I've accomplished."


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