Mackenzie Douthit has already said "I do" and is pregnant with baby No. 2! The 18-year-old "Teen Mom 3" star announced that she and fiance Josh McKee have already tied the knot and are expecting their second child together.

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According to The Daily Mail, the MTV star from Miami, Okla. initially shared her pregnancy and marriage news in a Facebook post on Monday, Aug. 12, writing, "And yes. For everyone wondering, I'm 12 weeks pregnant, time to tell the truth."

She then took to Twitter to respond to haters, arguing, "Been married for months but I'm not allowed to get pregs with my husband without Miami girls subtweeting . . . do I look like I care????" She added, "Im married yall and happier than all of you. God knows what he is doing . . . get a life . . ."

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Douthit and McKee appeared on season 4 of "16 and Pregnant" and are already parents to nearly 2-year-old son Gannon. The high school sweethearts announced in January this year that they were engaged for a second time after calling things off in October 2012.

The second-time mom-to-be also wrote on Facebook Monday, "Yes I love everyone checking on me, but yes I have reached my breaking point and have literally been through hell and back these last three days. I have kept this a secret because I'm probably the easiest target of all miami to judge. I only told cause people are asking why I'm fat lol.... So I'm not texting anyone back right now I need some time to myself. So sorry if ur mad cause I'm not texting back. Or mad cause you didn't know about this . . ."

On July 22, Douthit posted a photo on Instagram of herself flashing her stomach in a bathroom mirror. "You can tell I haven't done any hard workouts lately. Lol," the cheerleader wrote. "Hoping cheer camp gets me motivated ton get in better shape."

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Though Douthit said she's been married "for months" in her Aug. 12 tweet, the "Teen Mom 3" star posted photos from her bachelorette party on Aug. 9. The next day she tweeted, "Lets just say . . . I've had the time of my life tonight. Love my life and love all my girls and . . . IM GETTING MARRIED."

"Teen Mom 3" premieres Monday, Aug. 26 at 10:00 p.m. EST on MTV.


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