Roddick, a 34-year-old retired tennis star, announced Saturday at the International Tennis Hall of Fame Class of 2017 ceremony that Decker, a 30-year-old model and actress, is pregnant with a baby girl, according to People.
"You're my partner in crime," the former tennis pro said of Decker during his acceptance speech.
"In a life full of good fortune, being around you has been by far the luckiest part. I'm a better human for us having met 10 years ago."
"Brook, I don't know how you juggle it all," he added. "[Our son,] Hank, will someday realize how lucky he is. Our daughter that's coming will also realize she has the best mother on earth. Simply, thank you for being you."
Decker's company, the wardrobe organizing website Finery, confirmed the news in a post Sunday. The company shared a photo of the star wearing a mint-colored plaid dress while cradling her baby bump.
"From @brooklyndecker to our team here this morn: 'HEY GUYS....OUR FINERY TEAM JUST GOT A NEW USER!' We [love] u B & Andy!" the company wrote.
Decker and Roddick married in 2009, and welcomed son Hank in September 2015.
Decker, who is known for her modeling work with Sports Illustrated and for playing Mallory Hanson on "Grace and Frankie," told Refinery29 in March that she balances motherhood and her career with "help."
"Quite frankly, I have help. I have a nanny. I have a wonderfully supportive husband," the actress said. "I'm lucky to be allowed to go and work because I have support at home."
"Moms need help, and I don't think anyone should be ashamed of that, whatever form it comes in," she added.
"I know that without childcare and a supportive spouse, and friends and family who love spending time with my child, there's no way I'd be able to balance it all."
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