Kristen Bell and Dax Shepard Announce their Daughter's Arrival on Twitter

Kristen Bell is the proud mom of a cute girl.

The "House of Lies" actress and her fiancé Dax Shepard welcomed their first child, Lincoln Bell Shepard, Thursday, March 28.

The proud father announced his daughter's arrival on Twitter.

"Lincoln Bell Shepard is here. She has mom's beauty and dad's obsession with breasts. Hooray!!!"Shepard wrote, while sharing the happy news with his 388,344 followers on Twitter.

The new mom, overwhelmed with her new status, instilled some humor while explaining her new role as a mother.

"My new roomate poops her pants and doesn't pay rent...basically @daxshepard1 pre-sobriety :) welcome baby Lincoln xo" she wrote.

The proud parents' Twitter account has been flooded with congratulatory messages from their fans and well-wishers since then.

"Congrats!!  And so cool to name your kid after Daniel Day Lewis!!" one of the  followers, told Bell.

Shepard and Bell, started dating in 2007, got engaged in 2010 and announced their plan to stay unmarried until the state of California made same-sex marriage legal.

"The reason we're not rushing to get married is because I don't feel appropriate taking advantage of a right that's denied to my [gay and lesbian] friends," Bell told Daily Mail last year.

So the couple announced their decision to become parents before tying the knot.

"We'll do it. We'll have some babies," she told Us Weekly in January 2012, about her baby plans. ""It will be our gift to America."

Bell started her acting career as Becky Thatcher in "The Adventures of Tom Sawyer" in 2001 and grabbed many awards including the Satellite Award and Saturn Award. Currently, she is playing the female lead role on the television series, "House of Lies."

Shepard appeared with Jessica Simpson in "Employee of the Month."  Presently he's playing a lead role in NBC's "Parenthood."