The couple tied the knot on Friday, nearly a year after Foster proposed.
McPhee, 35, and Foster, 69, wed in London at the Church of Saint Yeghiche in South Kensington, where the bride wore a wedding gown by Zac Posen and the groom wore a tuxedo by Stefano Ricci.
Around 150 guests including designer Posen, as well as close family and friends, were in attendance. All of Foster’s kids were on hand including eldest daughter Amy, who recently revealed she was diagnosed with breast cancer and will undergo a double mastectomy operation.
This is the second marriage for McPhee and fifth marriage for Foster, who was most recently married to Real Housewives of Beverly Hills star Yolanda Hadid after ex-wives B.J. Cook, Rebecca Dyer and Linda Thompson.
Hours before the wedding, McPhee shared a video of her pre-wedding beauty prep, posting an Instagram Story of herself getting a facial.
“The secret to a calm and collected bride,” she captioned the clip. “And maybe a little Xanax.”
On Friday, just before the ceremony, her new daughter-in-law Erin Foster, 36, shared a video to her Instagram Story featuring herself and her family dressed up in the car, winking playfully at the camera. Erin’s sister Amy, 45, also shared a video of herself receiving an IV drip. “She ready for the wedding!” read the text on the clip.
The American Idol alum posted a tribute to her new husband on Friday with a throwback video of the pair performing “Somewhere Over The Rainbow.”
“Exactly 13 years ago today my very first single, Somewhere Over The Rainbow, was released right after Idol,” she wrote. “Today… I’m marrying the man who produced it. Life is full of beautiful coincidences, isn’t it? Thank you for taking me over the rainbow, David.”
Ahead of their nuptials, the couple had been embarking on a trip across Europe, posting photos in Mykonos, Greece, and Lake Como, Italy.
McPhee recently shared a series of snaps, taken by Foster, of herself wearing a latte-colored bikini while aboard a yacht in Mykonos. The swimsuit shots came after the Waitress star posted a fun slideshow of photos that featured her on the boat — drink in hand — in an ‘80s-inspired get-up.
The engagement ring has special significance for McPhee because it reminds her of more than just her happy future: it makes her think of the last conversation she had with her late father, who died just weeks after she was proposed to.
“He was so happy for me,” the Waitress alum shared on Instagram. “My ring was the last thing I showed my dad before he passed and makes me smile when I look at this as a reminder of our last conversation. … My love wisely said to me the other day that ‘death is the only thing that is 100 percent inevitable and the thing we are least prepared for.’ So today we’re celebrating life and not forgetting love.”
Following the engagement confirmation in July, it was revealed that Foster played piano at McPhee’s February 2008 nuptials to her first husband, Nick Cokas. The Grammy-winning songwriter and producer was seen sitting at the keys behind the bride in PEOPLE’s exclusive photos from her nuptials.
After consistently avoiding addressing dating rumors, McPhee and Foster were first romantically linked in May 2017 when they were spotted enjoying a PDA-filled dinner date at Nobu in Malibu.
Then in May, the couple finally confirmed they were indeed an item when they attended the Met Gala together.
McPhee and Foster have been friends for years after first meeting on the set of American Idol when McPhee was a contestant in 2006. She previously collaborated with her soon-to-be husband for a few live performances, including his 2008 PBS tribute concert Hit Man: David Foster & Friends.
She’s also well-liked by Foster’s daughters Erin and Sara, 38.
“Excited about my new stepmom,” Erin jokingly shared on her Instagram Story in December 2017, also adding: “My parents.”
A month before, Erin told PEOPLE, “[Katharine]’s amazing. I really like her. She’s awesome. My dad is kind of a hopeless romantic, and Katharine’s awesome. We really, really like her, and we’ve known her for a really long time. And if he’s happy, we’re happy.”
And in July, a source told PEOPLE that the Barely Famous stars “love Katharine.”
“Of course they joke about the age difference,” the source said of the sisters who are both older than McPhee. “She’s so sweet and really gets along with the family. She’s spent a ton of time with them. No one has anything bad to say about her.”