Kim Kardashian is Expecting!

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The rumors are true: Kim Kardashian is pregnant! The reality star's rep confirmed the news to ET after Kim's boyfriend Kanye West announced it Sunday night during his concert in Atlantic City.

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Kim took to her blog to share the exciting news. "It's true!! Kanye and I are expecting a baby," she wrote. "We feel so blessed and lucky and wish that in addition to both of our families, his mom and my dad could be here to celebrate this special time with us. Looking forward to great new beginnings in 2013 and to starting a family. Happy New Year!!!"

Kanye "announced" the news Sunday night, telling the crowd of more than 5,000 at the Ovation Hall at the Revel Resort in song form: "Now you having my baby." The crowd cheered with approval, and the rapper also told the audience to congratulate his "baby mom" and that this was the "most amazing thing."

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With the news officially out, a barrage of tweets from happy family members hit the Twitterverse Sunday night:

@KhloeKardashian: Keeping secrets is hard with so many family members! Especially when you are so freaking excited!!!!! LOVE is everything!!!!

@KrisJenner: Oh BABY BABY BABY!!

@KourtneyKardash: Been wanting to shout from the rooftops with joy and now I can! Another angel to welcome to our family. Overwhelmed with excitement!

@KendallJenner: whos excited about the KIMYE babbyyy?! :D weeee

@RealLamarOdom: I'm excited for Kanye and my sister! There's nothing like bringing life into this world! Let's keep Gods blessings coming!
@KylieJenner: Congrats to this beautiful couple. I love you guys

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Reports that Kim, 32, and Kanye, 35, began dating began to swirl in March of 2012. Rumors that Kim was pregnant and experiencing morning sickness started to hit the Internet a short time ago, with some reporting that Kim was just battling the flu. Guess not! The star is reportedly about 12 weeks along.