The actress is already mum to two daughters, Adelaide, 4, and Naleigh, 7, who she and her husband welcomed through adoption.
"Sooooo….the Kelley family received some very exciting news recently and I’ve been dying to share it with you all. We are expecting a third addition to our tribe! It was totally unexpected but thrilling nonetheless," she wrote on her blog.
"Naleigh and Adalaide are over the moon and can not wait to spoil their new sibling rotten and of course Josh and I are full of high hopes and bubbling anticipation. The whole pregnancy thing is new to me but the thrill of having a baby is not....I wasn’t sure pregnancy was even in the cards for us. Turns out it was very much in the cards!"