Katharine McPhee and David Foster 'Argued' Over Song Choice for Their New Joint Holiday Album

Katharine McPhee and David Foster gave a candid glimpse into their relationship during an interview published on Thursday, October 5.

When discussing their new single "Amazing Grace," which will be released as part of the second half of their Christmas Songs album, they shared how the process caused some tension in their relationship.

"We argued a little bit, not in the bad way," McPhee admitted of the song, which will debut on October 20. "It's a bit of a debate over whether we should do 'Amazing Grace' because I said, 'It's not a Christmas song, it's a religious song.' The label ended up actually really liking it because we're using it as our first single to kind of get out there, kind of earlier before the whole Christmas craze without it beating you over the head that it's a Christmas song. So it's actually kind of cool that we did it."

"We got a nice response from the first seven songs so we thought, 'Oh, people are kinda digging this,'" Foster chimed in.

"Volume two, we'll just complete the whole thing," McPhee said. "A couple of my girlfriends are like, 'You're doing another Christmas album?' I'm like, 'No, this is a completion of the first Christmas album.'"

On top of working on the highly anticipated joint album, the married couple has been on the road for the David and Friends Tour. The performances will continue in North America next month.

"It's been great," the 73-year-old said of traveling with his 39-year-old wife. "It's a bit of a shlep."

He continued: "Being together has not been the shlep. Just the constant packing and unpacking. You wake up in a new city every day and it's just a grind. That's the only part that sometimes wears on you. And you just want to be in your own bed. But when we're onstage for those two hours it's the best part of the whole thing."

The duo also discussed how they'll be spending their holidays, when they will finally be off the road.

"We started this tradition in the desert of having all of my family and all of her family together. We would rent a house," Foster said about Thanksgiving. "And we did that last year. We're gonna do it again this year."

Never miss a story — sign up for the OK! newsletter to stay up-to-date on the best of what OK! has to offer. It’s gossip too good to wait for!

"We just have a great weekend with playing tennis and pickleball and the family's all together and we do two big meals," he noted. "And then for Christmas I don't know, like, we're gonna be in this new house and we're gonna have new memories to create."

ET reported on McPhee and Foster's comments.