Katharine McPhee is sending an abundance of positive vibes to her musician husband David Foster on his 70th birthday.

The “American Idol” runner-up married the legendary music producer and composer in late June of this year in a princess-like affair in London and “struggled to fight back tears” in her custom-made Zac Posen gown and as it appears, the 35-year-old couldn’t be happier with her decision to marry the man she met way back in 2006 while she was a guest mentor on the hit competition series.

I’ve known this man for 13 years now! What was once a working relationship became a friendship and ultimately led us here,” McPhee wrote on Thursday in an Instagram caption as she chronicled the pair’s love in series of photos.

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“Anyone who meets him talks about how charming he is, so much so that he eventually charmed his way into my heart. I’m so proud that he’s my husband! May God bless you with many many more years. Happy birthday baby! @davidfoster 🎈🎉🎁.”

The Broadway star opened up about her new marriage to Foster in an August interview with Entertainment Tonight and revealed that she decided to take on the Canadian musician’s last name because she’s a “romantic.”

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“I’ve always liked the idea that it’s still a traditional thing that exists in our society,” she said. “I like the idea. I think it’s romantic and it’s a great last name.”

Katherine McPhee and David Foster, pictured here in May, tied the knot in London on Friday.

Katherine McPhee and David Foster, pictured here in May, tied the knot in London on Friday. (Bennett Raglin/Getty Images for Breast Cancer Research Foundation, File)

The “Smash” star and also raved that her marriage to the 16-time Grammy-winning producer has been a piece of cake thus far.

“We just love being with each other. There’s no arguing, no drama. It’s just easy,” she shared. “That’s how it should be.”

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Despite the couple’s 34-year age gap, the pair began dating in the spring of 2017 but didn’t confirm their relationship until almost a year later when they attended the Met Gala together.

Foster previously admitted that the brunette bombshell didn’t quite catch his eye initially, but over time the duo became inseparable.

“She didn’t catch my eye on the first day because I was so busy trying to do my job,” Foster explained. "But the reality is that in the last 12 years I’ve always had a connection with her.”

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Oddly enough, Foster also played piano at McPhee's 2008 wedding to Nick Cokas. She and Cokas divorced in 2014.

McPhee is Foster's fourth wife. His most recent bride was "Real Housewives of Beverly Hills" star Yolanda Hadid, from whom he separated in 2015 and divorced in 2017.

Fox News’ Jessica Sager and Mariah Haas contributed to this report.