As the daughter of TV mobster Tony Soprano, Meadow is a bona fide "wise girl." But these days, actor Jamie-Lynn Sigler, who portrays Meadow in HBO's blockbuster The Sopranos, is showing her smarts in real life.

Sigler, now 21, is promoting her new book Wise Girl: What I Learned About Life, Love and Loss (Pocket Books). The book addresses not only her struggle with and triumph over an eating disorder, but also describes the support of her television family during her ordeal. 

"What I've learned is that for someone recovering from an eating disorder, it's like a pendulum," she said. "You have to go back and forth until you find your balance. Unfortunately, with me, it was in front of millions of viewers." 

How did it all begin? 

Sigler had shot The Sopranos pilot, when she was at normal weight, the summer right before she started her junior year of high school. The series' first season, however, did not begin production until almost a year later. 

In those intervening months, Sigler fell ill for the first time. Her ability to lose extreme amounts of weight was a revelation. "It was something you could have absolute full control over," Sigler said. 

By the time Sigler arrived on the set to begin shooting the first season, she was already at the beginning of her recovery. But, to most cast members, she looked like a shadow of her former self. 

"Size zero's were too big on me, so obviously people knew there was a problem," she said. 

"I remember Jim Gandolfini took my arm and wrapped his whole hand around it," Sigler said. "And he was, like, 'Are you eating?' " 

She told him she was fine. 

"He could tell I didn't want to talk about it, so he left it alone," she said. 

In the book, she reveals that the show's creator, David Chase, even phoned her mother to ask about her health and she voices her concerns that she might be replaced. 

Only during the second season did Sigler open up to her TV family. "It took me that whole year to come to terms," she said. 

At that point, Sigler began speaking publicly about her illness, even going on The View to make her first on-camera announcement. 

When Gandolfini heard Sigler had gone public, he also reached out. Sigler recalled: "I remember one day on the set, we were sitting on the couch and he said, 'You know, I think it's really great what you're doing, talking out about what you went through, because it's hard to put yourself out there to help other girls.' " 

Sigler said her openness with the rest of the cast sealed her friendships , especially with Aida Turturro, who portrays Janice, Tony's sister. 

Turturro was introduced to audiences in the second season, the same time critics came down hard on Sigler for now appearing too heavy. 

"Everyone would have been there for me, but Aida was the one I really turned to and the only person I would cry to," Sigler said. "You need to feel confident and happy about yourself and Aida taught me that." 

Other male cast members provided verbal support with a wink of an eye. "They're like real Italian guys, so they're like: 'We want meat on you, Jamie,' " she said. 

These days, however, what looks meaty is Sigler's future. 

The Sopranos fourth season begins Sept. 15, and Sigler reveals Meadow is still reeling from the death of Jackie Jr. 

"It definitely affected her," Sigler said. "You kind of find out emotionally where Meadow's at. 

"She moves on, focuses a lot on school, starts to volunteer. And she's getting closer with her family."

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