When Katharine McPhee and Meghan Markle were teens growing up in Los Angeles, they became friendly through musical theater.

Last week, the two reunited at WE Day in London and even though it's been years since they've seen each other, the Duchess remembered the “American Idol” alum.

McPhee, 34, told the Evening Standard, “She was lovely, and she remembered me – she remembered my sister more specifically because they were in the same class – and she said, ‘I’m just sitting around waiting for the baby to come.’”

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The singer/actress then told Good Morning Britain that she and Markle did take a photo together but she hasn’t been able to locate it because “you know, the royals have to approve everything.”

McPhee is across the pond to star in London’s production of "Waitress." She previously played the lead role of Jenna on Broadway.

McPhee added on the UK morning show that she would love if the Duchess of Sussex and her husband came to the show – “I’m hoping she will, and I’m going to invite her through some mutual friends.”

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The Duke and Duchess are definitely theater lovers. Over the past year, the two have attended performances of “Hamilton” and “Tina – The Tina Turner Musical.”

Back in January, McPhee shared a throwback picture on Instagram of her smiling with the Duchess of Sussex.

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“Meghan and I did musicals together as kids. She grew up to be the Duchess of Sussex and I grew up to star on the West End, so same life if you ask me. #TBT,” she captioned the pic.