Jessica Simpson is having her second baby -- and she once again revealed the news in a splashy holiday tweet.

In October 2011, the singer/actress [article id="1673485"]confirmed pregnancy rumors[/article] by tweeting a photo of herself dressed up for Halloween with the caption "It's true -- I'm going to be a mummy!" In the spring, Simpson and fiancé Eric Johnson welcomed [article id="1684216"]daughter Maxwell Drew Johnson[/article] to the family.

This time around, also after a month of pregnancy rumors, Simpson tweeted a photo of Maxwell with the phrase "Big Sis" written in the sand in front of her. "Merry Christmas from my family to yours!" Simpson wrote, along with the Christmas Day pic.

Maybe for their third pregnancy, Simpson and Johnson can spell out the baby news in a fireworks display on the Fourth of July?

[article id="1684272"]Maxwell isn't the only newsmaking celebrity baby![/article]

[article id="1686063"]Baby Maxwell was unveiled to the world[/article] back in May on the cover of People magazine along with a story about Simpson's new "full-on job" as a mom. "From how I sleep to what I think about, Maxwell has definitely taken over everything," Simpson told the magazine. "We stare at her all the time. We can't get enough!" Simpson also referred to Max's birth as "the greatest experience of our lives."

Simpson began dating retired NFL player Johnson in May 2010, and the couple announced their engagement in November of that year. Their courtship followed Simpson's tabloid-target [article id="1615731"]romance with Dallas Cowboys quarterback Tony Romo[/article] and her three-year marriage to 98 Degrees singer and "Newlyweds" co-star Nick Lachey.

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