“Mom, Dad and son are all doing wonderfully,” they told PEOPLE in a statement.
In October, OK! reported that the 36-year-old performer and the 71-year-old record producer were expecting their first child together. The pair never publicly announced the news, although they were spotted browsing baby stores together in Montecito, Calif., with McPhee showing off a clear baby bump.
That same month, the Smash star also dropped major hints on social media that her family was growing.
“I just came home and opened this gift from Aperol Spritz, which for those of you who don’t know … it’s one of my favorite drinks and reminds me of being in Capri,” McPhee said on her Instagram Story at the time. “Thank you, Aperol Spritz. I won’t be drinking this anytime soon, wink, wink. But I’m very excited! Who’s coming over for an Italian-inspired cocktail?”
The singer previously alluded to her pregnancy during a performance of "She Used to Be Mine" from the Broadway show Waitress during the virtual Glow 2020 event. During the song, the brunette beauty cradled her growing belly while singing "and the life that's inside her, growing stronger each day."
McPhee and Foster tied the knot in London in June 2019 after first meeting in 2006 when he appeared on American Idol as her mentor. One of Foster's five daughters Erin Foster, 38, told PEOPLE last year that she and her sisters jokingly call McPhee "Mommy."
"Interestingly, the age difference has played a role in a positive way," Erin dished. "Our dad comes from a generation where women are more passive. He is also passive about his feelings. Kat has really pushed him to open up. We could get into a fight, and then Kat's like, 'No, you have to pick up the phone, call your daughter back.' She's a facilitator, which is really important. She pushes him to be more emotional and more vulnerable."
Despite a 35-year age difference, the Hollywood stars are in it for the long haul. “The fact that we just really love being with each other,” McPhee told Entertainment Tonight in August 2019. “There’s no arguing, no drama. It’s just easy. That’s how it should be.”