Jessica Simpson flaunted her slimmer figure when she visited Good Morning America on Tuesday for her first live interview since giving birth to her second child Ace Knute.

"I believe in it with all of my heart," she told GMA lifestyle anchor Lara Spencer about Weight Watchers. "It's a lifestyle. I've tried so many different diets, and you can only stick to something for so long and I feel like with Weight Watchers, it just becomes a part of who you are."

The singer turned fashion designer spoke about her first pregnancy with her daughter Maxwell (now 20 months old) and said she didn't focus much on her weight. However, when she was pregnant with her now 6-month old son she made sure to watch what she consumed.

Yet, Simpson, 33, who wore a tight black dress, also made it clear that it's important for women to love themselves and not give in to the pressures of society.

"As a mom, I just have this confidence and I just feel so proud of what I've done and what I've accomplished," the Weight Watchers spokesperson said. "And I really do also feel this need to just be the best role model for my children... I want [Maxwell] to look up to me and want to be like me."

Aside from her weight loss and children, Simpson also spoke about her fiancé Eric Johnson, whom she plans to wed sometime this year.

"We don't have an actual [wedding] date, but we do know that we want it to be this year," she said. "We need to get married."

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