Diablo – whose real name is Brook Busey – announced the baby news on Twitter on Tuesday.
"Thanks for the congrats on my fetus," the 31-year-old Tweeted. "No secrets here; just thought it would be fun to see how big I could get before someone noticed."
This marks the first child for Diablo and husband Jon Hunt.
Diablo's "United States of Tara" is currently airing its second season on Showtime and the screenwriter is also busy adapting the "Sweet Valley High" book series into a movie.
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