The actress shared her exciting baby news on Instagram, while treating fans to a slew of pictures from her recent baby shower.
In one snap, Kaya can be seen holding a balloon that spells out boy, while her husband Benjamin Walker wraps his arms around her growing bump.
Alongside her post, Kaya told her followers: "I have the most wonderful friends in the world. Thank you @paige167h @hanshan_x @xleahx4 for throwing us an amazing surprise baby shower. We love you, and so will your future nephew!!"
She first revealed she is pregnant back in June, subtly announcing she and Ben are starting a family together by sharing a loved-up photo of the pair.
Kaya and Ben were pictured on the beach, holding onto her stomach. She captioned the shot: "I love you @findthewalker I love our little family." And Kaya added three emojis, one of a couple, another of a baby and one more of a puppy.
Ben, meanwhile, gushed: "Happy summer from the four of us.. I love you @kayascods."
News Kaya and Ben are set to be parents comes a year after they married in New York City Hall back in March 2015. The pair actually tied the knot twice, having another wedding day in front of family and friends later that year in December.
They recently jetted off to Santorini, Greece for a babymoon together, with Kaya telling fans she'd had the "perfect babymoon" with Ben overseas.
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