Maci Bookout of 'Teen Mom' fame is going to be a mom again! The 23-year-old is expecting with her boyfriend Taylor McKinney, a source tells Us Weekly.

Bookout's 6-year-old son, Bentley, was born in 2008 to her and her then-fiance Ryan Edwards. The young couple from Chattanooga, Tenn., appeared on MTV's '16 and Pregnant' and its spin-off 'Teen Mom.' Bookout and Edwards split during filming of that series, although Edwards remains an active father to Bentley.

The pregnancy came as a happy surprise to Bookout and McKinney, who have been together for several years. "We still can't believe it," she tells InTouch Weekly. "It was a huge shock, but we're very excited."

The baby is due in June. The proud parents-to-be recently welcomed another new addition to the family over the holidays: A puppy named Bonnie.

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