The outing comes shortly after news broke that McPhee is pregnant with her and Foster's first child together.
Prince Harry and Meghan Markle reunited with Katharine McPhee and David Foster. The Duke and Duchess of Sussex were photographed heading to a double date with the pregnant actress and her music producer husband this week.
The former Suits star wore Club Monaco’s Reissue trench coat with a camel-colored top, black trousers and orange mules. She completed her look with a black Stella McCartney purse and a face mask. Harry, 36, opted for a white button-down, dark pants and brown shoes. The couples dined at Lucky's Steakhouse in Montecito, California, where Harry Meghan, 39, have settled into their new home.
Meghan and Katharine, 36, have known each other for years. The American Idol alum went to Immaculate Heart Middle School while her older sister, Adriana, attended the companion high school with Meghan in Los Angeles.
Last year, Katharine posted a throwback photo of herself with Meghan during their time doing "musicals together."
David, 70, also helped the couple find their secluded holiday getaway home in Vancouver Island, Canada, at the end of last year. Harry and Meghan stayed at a $14 million, 11,416 square foot, five-bedroom, eight-bathroom North Saanich location, owned by the musician's close friend, whom he declined to name.
"I felt honored that I was able to help Meghan there, because I'm a Canadian and we're a commonwealth country, we're the Crown's," David told the DailyMail in January. "It's important to us, so I grew up with that kind of sentiment. I was really happy to be able to help them to find a respite just to take a little time off."
Meanwhile, a source confirmed to ET on Thursday that Katharine is pregnant with her and David's first child together.
"Katharine and David are expecting their first child together and the couple is very excited," the source told ET. "Katharine and David discussed having kids early on and were on the same page."
This is the Smash star's first child, while David has five daughters -- 34-year-old Jordan, 38-year-old Erin, 39-year-old Sara, 46-year-old Amy and 50-year-old Allison -- from previous relationships.
Hear more in the video below.
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