Kailyn Lowry is ready for baby No. 2! The Teen Mom 2 star is expecting her first child with husband Javi Marroquin, multiple sources confirm to Us Weekly.

"Kail is pregnant," a source confirms to Us.

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Lowry, 21, tied the knot with the U.S. airman back in September after a year of dating. The MTV starlet is already mom to son Isaac, 3, with ex-boyfriend Jo Rivera. 

"They are overjoyed to give Isaac a sibling," a second insider tells Us. "Kail is thrilled!"

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Lowry, who recently revealed she has been diagnosed with bipolar disorder, is planning a second, larger wedding celebration with her husband in the future. But the Teen Mom 2 star announced on March 12 that they decided to postpone the party until 2014.

"Looks like we'll be pushing the wedding back an entire year," she tweeted. "Just not in our budget this year like we planned. Taxes."

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Lowry has yet to comment on her second pregnancy, but tweeted Tuesday, March 26 that she's "just happy."

This article originally appeared on Usmagazine.com: Kailyn Lowry Pregnant: Teen Mom 2 Star Expecting Second Child