Maci Bookout hasn't needed to use diapers and baby bottles for quite some time, but that's about to change: The "Teen Mom" cast member is expecting her second bundle of joy!

The Tennessee native and her longtime boyfriend Taylor McKinney will welcome their precious peanut in June, Bentley's mama confirms to "In Touch." And this pregnancy was a very big, and unexpected, surprise.

"We still can’t believe it," Maci told the magazine after disclosing that doctors advised her that her polycystic ovary syndrome diagnosis (PCOS) made the chances of having more children very slim. "It was a huge shock, but we are very excited."

Maci memorably welcomed her beautiful boy on the very first episode of "16 and Pregnant" back in 2009. And now, the little man of many talents is going to be a big brother.

"I didn't think that another pregnancy was possible," the 23-year-old admitted.

Maci's bun in the oven will also have a playmate very close in age: Catelynn Lowell is due to give birth to a petite princess in a few short weeks!

+ Offer your congrats to Maci, Taylor and Benny, and be sure to keep checking MTV News for updates about the wee one on the way! And before Maci's return to MTV in 2015, relive Bentley's emotional birth on "16 and Pregnant."