David Foster and Katharine Mcphee's Relationship Timeline

David Foster and Katharine McPhee are a musical match.

They first met on American Idol in 2006 when McPhee was a contestant and Foster was a guest mentor. They became friends — Foster even played the piano at McPhee's first wedding — and it was seemingly all platonic until rumors about a romantic turn began to fly in 2017.

Foster and McPhee made their red carpet debut as a couple in 2018 and tied the knot a year later. They welcomed a son, Rennie David, in 2021.

The Grammy-winning producer has embraced fatherhood again — he has five daughters from previous relationships — saying that "it's just great being a dad," while McPhee has referred to motherhood as the "greatest job" she will ever have.

From their first meeting on TV to days out with their son, here's everything to know about David Foster and Katharine McPhee's relationship.

2006: David Foster and Katharine McPhee first meet on American Idol

Foster and McPhee have known each other since 2006 when McPhee was a contestant on American Idol. Foster was a guest mentor on the show and worked with McPhee, who later finished as runner-up, as she prepared to sing Whitney Houston's "I Have Nothing," a song Foster co-wrote.

After they met, Foster told cameras that McPhee had a "great, great future ahead of her." Fellow guest mentor Andrea Bocelli said, "You have to say also, she's nice, beautiful and young," to which Foster nodded and laughed.

February 2, 2008: David Foster plays piano at Katharine McPhee's wedding to Nick Cokas

In 2008, McPhee married actor and producer Nick Cokas at Beverly Hills Presbyterian Church, where Foster was in attendance. He played piano to accompany McPhee as she sang Natalie Cole and Nat King Cole's "Unforgettable."