David Foster and Katharine McPhee may be involved with what appears to be an enjoyable romance, but the American Idol alumna likely won't become Mrs. Foster.

Although the music producer, 68, and his younger girlfriend, 33, are "enjoying the bond that they share right now," an insider recently spoke to E! News about their relationship, claiming that while they are healthy and in a good place, Foster isn't too keen on the idea of walking down the aisle for a fifth time.

"David has not shown any interest in getting married again. He hasn't discounted how he feels about Katherine but there are no plans for them to even get engaged anytime soon," the source explained on Jan. 10.

As for how McPhee feels about the idea of continuing on with her relationship without a promise for a future marriage, the insider said that the singer isn't pushing the idea of marriage and all and is quite content with how things are between them.

Foster has been married four times and has a total of eight children. Among them are actresses Sara and Erin Foster, who were recently named as the creative heads of Bumble Bizz.

According to E! News, Foster's daughters frequently joke that if their father does get married, he will definitely need to have a strict prenuptial agreement for his fifth wife.

While Foster has made a habit of getting married, McPhee has been married just once. As E! News revealed, McPhee was married to Nick Cokas from 2008 to 2016 and has been linked to Foster since May of last year.

Although things between Foster and McPhee didn't become romantic until recently, they've known each other for over a decade, and now they are said to be "more serious" than ever about their romance.

"Katharine has always had a crush on David, and she's happy," a source explained.

The insider went on to say that while Foster is usually a bit of a playboy, being with McPhee has led to a change in his behavior, and he's reportedly quite comfortable when he's around her.

Last month, in Health magazine's December 2017 issue, McPhee claimed to be nothing more than "good friends" with Foster but added that she is extremely fond of the producer. She also applauded Foster as an "incredible person" and said she had known him since she was 21 years old.