MICHAEL SIMON / StarTraks 1 / 15
MICHAEL SIMON / StarTraks 1 / 15

Bada-bing, it's a boy! First-time pregnant Jamie-Lynn Sigler is having a son, she revealed to pals during a baby shower on Monday (March 25) an insider confirms to Us Weekly. Expecting her first child with fiance, baseball player Cutter Dykstra, the "Sopranos" and "Guys With Kids" actress, 31, surprised her friends with the big reveal at the bash, held at a friend's L.A. home.

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To celebrate, Sigler treated her pals to Sally Hansen Nail Color Manicures -- and, in honor of her son-to-be, customized her own manicure with a shade a of blue, with a baseball on her pinky finger.

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"She is so excited to be having a baby boy!" the insider reveals. Sigler and Washington Nationals infielder Dykstra, 23, debuted their romance back in March 2012. The slugger proposed with a huge diamond engagement ring in late January. It will be the first marriage for Cutter (whose dad is former Mets star Lenny Dykstra) and the second for Sigler, who was married to her manager A.J. DiScala from 2003 to 2005.

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"Jamie couldn't be happier. Cutter is the perfect guy for her," another source told Us of the couple. "Although they have only been together for a year, they both know that this is it for both of them. They are


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