Jersey Shore alum and Snooki & JWoww star Jenni 'JWoww' Farley has revealed that she and Fiance Roger Mathews are expecting a baby girl.

The couple, who first announced Farley's pregnancy around Christmas, recently learned the news of their baby's sex, and they couldn't be happier.

"I pictured a boy this whole time, so when I saw 'girl' on the paperwork, I was like, 'no way!' But deep down I think I knew," the 27-year-old reality star told Us Weekly. "[Snooki's son] Lorenzo is gonna have a BFF, and I couldn't be happier!"

"She will be my best friend and daddy's little girl," she added. "I can't wait for everything from her first steps to her first dance class."

Farley, who is already the godmother of Nicole 'Snooki' Polizzi's son, Lorenzo LaValle, has been engaged to Mathews, 37, since September 2012.

Polizzi has already expressed her excitement over her best friend's news on twitter, writing on Jan. 22, "YAY finally I can go shopping with @JENNIWOWW for BABY GIRL THINGS! Lorenzo's so excited!!"

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Though the news does excite Farley at the moment, she has admitted that she now fears her daughter's teenage years thanks to her own famously dramatic ones.

"I was a teenage girl once, and boy, do I know how sneaky we can be! Karma is going to kick me in the butt with her!" Farley said.

Farley, a Franklin Square, N.Y. native, rose to fame on the hit MTV show about young "guidos" and "guidettes" living it up on the infamous Jersey Shore, in the town of Seaside Heights, N.J. back in 2009. She and Polizzi received their own spin-off show after the series wrapped in 2012.

The original show starred Farley, Polizzi (Marlboro, N.Y. native), Paul "PaulyD" DelVecchio (Johnston, R.I.), Samantha "Sweetheart" Giancola (Hazlet, N.J.), Vinny Guadagnino (Staten Island, N.Y.), Ronnie Ortiz-Magro (Bronx, N.Y.), Michael "The Situation" Sorrentino (Staten Island, N.Y.) and Angelina Pivarnick (Staten Island, N.Y.).

Pivarnick left the show after the second season, and was replaced with Deena Nicole Cortese (New Egypt, N.J.).