Inside David Foster's Birthday Dinner With Katharine McPhee: She Was "By His Side the Entire Time"

It looks like David Foster had a famous lady by his side to help celebrate his birthday—Katharine McPhee. 

The music producer and songstress were spotted as they headed out of West Hollywood hot spot Craig's in honor of Foster's 68th birthday dinner Wednesday night. According to an insider, the restaurant is the composer's favorite in the city and his daughters helped arrange the soirée. 

In addition to McPhee, attendees included his kids, Erin Foster and Sara Foster, and stepsons Brody Jenner and Brandon Jenner.  "It was a really nice dinner," the source described. "Everyone was joking around and giving him a hard time about his age, but David was loving it." As for the menu, the group enjoyed Craig's famous dessert, the chocolate pizza, as they sang Foster "Happy Birthday."

Meanwhile, the birthday honoree and McPhee looked "happy," according to the source. She was "by his side the entire time," the insider added. "David and her were affectionate. He had his arm around her at times and they looked happy."

Back in May, the two first sparked questions of a possible romance when they were spotted having an "intimate" dinner at Nobu in Malibu. 

"David was seen grabbing Katharine's face and kissing her cheek several times," an insider shared at the time. "Katharine was doing the same to David's face and they were acting as if they were a couple."