Naomi Campbell is making the most of her time in quarantine and interviewing celebrities on her YouTube series, “No Filter with Naomi.”

On Monday, the supermodel reminisced with fellow superstar Cindy Crawford about a birthday surprise they both participated in for Prince William back in the day. Princess Diana was behind it, of course.

Campbell said that she went to surprise the prince with Claudia Schiffer and Christy Turlington at Kensington Palace when he was 13 or 14.

“He was coming home from school and we had gotten there before he had gotten home from school and Princess Diana was like, ‘OK,’” Campbell recalled. “So we were just like, ‘What do we do?’ I mean, it was so sweet.”

“Did he blush when you met him?” Campbell asked Crawford, who said she met William a few years later, though the prince himself remembers it all a bit differently.

“I think he was 16 when I met him,” Crawford replied (Diana died when William was 15, so it would’ve been earlier).

“Look, I was blushing,” Crawford added. “I was so intimidated meeting Princess Diana and being at Kensington Palace and how just completely down-to-earth she was. And you know, because there’s so much protocol I guess, and not being English, I don’t understand some of it.”

Both models said that Diana opened the door for them, and likened their trip to the palace as “going to a friend’s house” because of the Princess of Wales’ demeanor.

“I feel like she was in jeans and, like, a cashmere sweater and almost that vibe of being super laid back,” Crawford said. “So I also was probably a little, I mean it was uncomfortable, but it was sweet. It was a very sweet day and a great memory.”

Campbell added that she “loved” Diana.

“Humble, how down-to-earth and I’m just blessed to know her for the time that I did,” the supermodel added.

William recalled the wild birthday surprise a few years ago, when he and Prince Harry participated in the 2017 ITV documentary “Diana, Our Mother: Her Life and Legacy.”

Anwar Hussein via Getty Images Prince William with Diana, Princess of Wales and Prince Harry on the day he joined Eton in September 1995.

“She organized when I came home from school to have Cindy Crawford, Christy Turlington and Naomi Campbell waiting at the top of the stairs. I was probably a 12- or 13-year-old boy who had posters of them on his wall,” William said at the time. “I went bright red and didn’t know quite what to say. And sort of fumbled and I think pretty much fell down the stairs on the way up.”

As Harry said in the documentary, “Our mother was a total kid through and through.” “When everybody says to me, ‘So she was fun? Give us an example,’ all I can hear is her laugh in my head,” he added. Subscribe to HuffPost’s Watching the Royals newsletter for all things Windsor (and beyond).