The couple are engaged, the actress and singer’s rep Leslie Sloane confirms to PEOPLE.
McPhee, 34, confirmed the news herself (via Ariana Grande gif and text with Just Jared founder Jared Eng) on social media, writing that 68-year-old Foster popped the question during their vacation to Italy, which they’ve been documenting on Instagram over the past few days.
“He did it at the top of this mountain in Anacapri. Totally dark, only stars. Thankfully he didn’t push me off the cliff. He said it was one or the other. And in the end he spared me,” she joked.
Later on Tuesday, Foster also confirmed on social media posting one of the many boat photos they have snapped of each other during their special vacation.
“🎼Yup!!,” he simply captioned the snap — though daughters Erin, 35, and Sara, 37, had more to say about their new (younger) stepmom. “Mommmyyyy,” Erin joked, while Sara wrote, “Out of the country. What did I miss?”
Prior to revealing the news, they took turns snapping photos of each other on a boat ride in Capri, which they posted on the site.
“Summer Daze part 2,” Foster captioned a shot of himself lounging in a white button-down shirt, khaki shorts and sunglasses, giving photo credit to his new fiancée.
McPhee also shared a post from the boat ride, slightly poking fun at her photographer.
“If only you saw the first 50+ pics it took to get to these two,” the American Idol alum wrote on Instagram.
TMZ was first to report the engagement news.
The musical pair first sparked romance rumors in September 2017, after the latter’s daughter Erin shared a photo of them together in Los Angeles.
While McPhee and Foster have been friends for years — first meeting on the set of American Idol when McPhee was a contestant in 2006 — Erin captioned the photo, “Excited about my new step mom.”
Asked about the relationship rumors, McPhee previously told PEOPLE that she had “zero desire” to address them. “It’s great that they want to do that. I think it’s so amusing that people are amused by my love life,” she added.
“Here’s how I look at it: I’m not doing anything wrong, so whether people think it’s true or false … there’s nothing bad happening in my life, so people can just say whatever they want,” she said.
The two have consistently avoided dating rumors, but have never shied away from public displays of affection and attending high profile events together.
This will be the second marriage for McPhee, who was previously wed to Nick Cokas, and the fifth for Foster, who was most recently wed to Real Housewives of Beverly Hills star Yolanda Hadid.