Foster became a father for the sixth time when he and McPhee welcomed their son Rennie in February 2021

David Foster opened up about welcoming a new baby in his 70s with wife Katharine McPhee.

The 72-year-old musician, who shares 1-year-old son Rennie with the 38-year-old singer, told People magazine that becoming a father again at his age was “not something” he expected but added, “I haven’t regretted a single day of it.”

“I’ve loved every single day,” the 16-time Grammy Award winner told the outlet.

He continued, “It’s the standard thing of like, ‘Oh, well, you were so young when you had your children and you were working day and night, you never saw them.’

“And there is some truth to that, sadly, for my [older] kids. I was just working a lot. Even though I’m working a lot now, I’ll cancel anything just to hang with him. It’s just different.”

Rennie is the sixth child for Foster and the first for McPhee. The record producer, who was previously married four times, is also father to daughters Alison, 52; Amy, 49; Sara, 41; Erin, 40; and Jordan, 36.

Foster and McPhee tied the knot in June 2019. The “Smash” alum told People she “hoped” to have a child with Foster but acknowledged that there were “no guarantees.”

In December 2020, McPhee confirmed speculation the couple was expecting their first child together when she posted an Instagram photo showing off her baby bump. The pair welcomed Rennie in February 2021.

On Father’s Day this year, McPhee shared a slideshow of photos featuring Foster, including an image of the Canada native holding Rennie while seated beside her on a couch.

“Happy Father’s to the man @davidfoster who loves me like I could have only dreamed of & who made me complete in life by making me a mommy,” she wrote in the caption.

McPhee continued, “I love our little family. I love our big family. You have NEVER complained over how your life is slightly different now. Well… you only complain that you can’t stay up late watching TV in bed but how can I blame you -that’s your favorite thing.

“You’ve only made bringing Rennie into the world an absolute joy for me. To many more adventures baby!”

Foster told People that he and the “Over It” singer “know we’re an unconventional couple” but they are certain that they belong together.

He pointed to Céline Dion and her late husband René Angélil, who also had a significant age gap.

The “My Heart Will Go On” singer was 12 when she first met Angélil, who was 38. He became her manager and the pair shared a close relationship which turned romantic when she was 19.

They wed in 1994 and were married for 22 years until his death due to throat cancer in 2016.

“With Céline and [late husband] René Angélil, there was a big age difference, and after I was working with them for a long time it just became Céline and René,” Foster told the outlet.

“It just looked and felt normal. But it was, of course, kind of odd in the beginning. But I think we’re over that hump now with five years of being together, and hopefully people just start looking like we belong together because we feel like we do.”

“Even if they don’t, we don’t care,” McPhee said. “We just love our history, how we met and where we are now. Sometimes we look at each other like, ‘This is so wild that we’re together.’”

McPhee and Foster first met in 2006 when she was a contestant on the fifth season of “American Idol.” Foster was serving a guest mentor and helped McPhee practice for her performance of the Whitney Houston song “I Have Nothing,” which he wrote.

McPhee said they “stayed friends through all these years.” They were first romantically linked in 2017 and got engaged after over a year of dating.

The two recently collaborated on a seven-track holiday album titled “Christmas Songs.” In December, they will embark on a six-city tour in support of the collection, which is set to be released Nov. 25.

McPhee joked that she “guilted” Foster into recording the album with her: “I said something like, ‘It’s really crazy I’m married to the greatest producer, basically of our lifetime, and I’ve only had you record me on a few songs.’ Then he said, ‘OK, well, why don’t we just do a Christmas album?’”

Foster said, “I love that we can do everything together. We really do like being together.”

“He just said that to me the other night: ‘We have so much fun together,” McPhee added. “It feels like we’ve been together 10 years — in a great way.”

Foster said that the couple isn’t sure if Rennie will follow in their footsteps and pursue a career in music. However, he noted that the infant is already developing his musical abilities on the piano and the electronic drum pad.

“We think [he’ll be musical], but we don’t know,” Foster said. “Kids, strangely, will do something for a while and then it’ll amaze you, and then they just drop it and they don’t do it anymore.

“So we don’t know if the drumming thing is here to stay — I’d rather he have a tennis racket in his hand than a drumstick, to tell you the truth. But anyway, if he ends up being a drummer, that would be great, too.”