Everything to Know About Katharine McPhee & David Foster's Relationship

The pair first met when she was a contestant on season 5 of American Idol in 2006, during which she was performed Whitney Houston's "I Have Nothing," which Foster wrote. He and Andrea Bocelli stopped by to help McPhee practice the song for the Top 6 show.

Foster, now 69, was a special guest at McPhee's previous wedding to Nick Cokas in February 2008. As seen in PEOPLE's exclusive wedding album, McPhee, now 35, performed her rendition of Natalie Cole's "Unforgettable" and Foster was seen behind the bride playing the piano. Then in May 2014, she filed for divorce from Cokas.

Though they avoided addressing any dating rumors, McPhee and Foster were first romantically linked in May 2017 when the two were spotted enjoying a PDA-filled dinner at Nobu in Malibu.

Foster's daughter Erin appeared to confirm the relationship by posting a photo of the couple to Instagram in September 2017 and said she was excited about her "new step mom."

"She's amazing," Erin, 35, exclusively told PEOPLE in October 2017. "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."

"I'm really, really fond of him, and I think he's an incredible person," McPhee said of Foster in her cover story for Health's December 2017 issue. "I've known him since I was 21 years old, you know? He produced my first single. So he's been really good to me. People can say whatever they want."

The couple finally confirmed they were an item when they walked hand-in-hand at the Met Gala in 2018.

Foster popped the question during their vacation in Italy in July 2018. McPhee's engagement ring was all the more sentimental as it was the last thing she showed her late father before he died.

In September 2018, the couple attended Celebrity Fight Night, where they performed "I Can't Help Falling in Love with You" with Andrea Bocelli, who told Foster on stage, "A few years ago, I told you she was The One," to which David responded, "You were right."

Despite their 34-year age difference, they're much more focused on all that they have in common. "There are just a lot of things when you look at the history of our relationship, neither of us could have written it," McPhee told PEOPLE. "I would never have imagined that this would be our future together."

"She didn't catch my eye on the first day because I was so busy trying to do my job," Foster told PEOPLE about their work on Idol. "But the reality is that in the last 12 years I've always had a connection with her."

The engaged couple were joined by McPhee's mom and sister on their island getaway to Hawaii.

In February 2019, McPhee penned a loving tribute to Foster, writing, "can't wait to marry you @davidfoster." Reposting the sweet image on his own feed, Foster sweetly captioned the image, "I won the lottery!!!"

The bride-to-be was surprised with a wild bachelorette party by her costars and friends in early May after her run in the musical Waitress in London.

Later that month, the couple were seen leaving a Beverly Hills courtroom, the site of Los Angeles' Marriage Bureau, but a source said "[this was] no ceremony," confirming that they were taking out a marriage license ahead of their big day.

The pair tied the knot on June 28, 2019 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.

Surprise! After saying "I do" last summer, the pair have reached another milestone moment: They are expecting their first child together, sources confirmed to PEOPLE on Oct. 8. 

The couple were seen shopping for baby items after grabbing lunch together in Montecito, California on Oct. 6. 

This will be McPhee's first child. Foster is already father to daughters Sara, 39, Erin, 38, and Jordan, 34, whom he shared with second wife Rebecca Dyer, and daughters Allison, 50, and Amy, 46, from previous relationships.