Advice between friends! Duchess of Sussex Meghan Markle has been giving pregnant pal Katharine McPhee tons of baby guidance as the singer prepares for her first child with husband David Foster, an insider exclusively tells Life & Style.

“Katharine is getting all kinds of useful baby tips from Meghan on what’s to come and she’s been practicing on Archie,” the source gushes over the A-list friendship. “She thinks he’s the cutest little boy ever!”

The former U.K. royal, 39, is even thinking of doing something special for the Smash star, 36, amid her first pregnancy. “Meghan’s talking about organizing a mini-baby shower for Katharine in Montecito,” the insider exclusively reveals.

It makes sense the former Suits star is doting on the American Idol alum during such a milestone moment in her life — the duo have been spending some quality time together lately. The ladies were spotted enjoying a dinner date with Meghan’s husband, Prince Harry, and Katharine’s beau, 70, in tow at Lucky’s Steakhouse in Montecito on Tuesday, October 6.

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In fact, the royal and the actress have a long history. They both attended the same school growing up but weren’t friends during their education. However, they reconnected when Meghan became part of the royal family as Katharine was starring in the musical Waitress on the West End at the time.

“Meghan and I did musicals together as kids,” Katharine wrote in January 2019 on a throwback photo of the pair in costume during a performance years prior. “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.”

Sources confirmed to People the vocalist and the composer were expecting their first child together on Thursday, October 8. “Katharine is enjoying being pregnant and she’s even more excited about meeting the baby!” an insider told Life & Style exclusively. “The pregnancy is the best thing that’s happened to her all year. David is thrilled, too. He can’t believe he’s going to be a dad of six!”

The music executive is already father to daughters Sara, 39, Erin, 38, and Jordan, 34, from his second marriage to ex-wife Rebecca Dyer, as well as two daughters — Allison, 50, and Amy, 46 — from previous relationships.

“Obviously Katharine is slightly nervous about being a first-time mom,” the insider continued. “Fortunately, David had lots of experience and is putting her mind at ease! He knows she’ll be a complete natural and says she has nothing to worry about.” Clearly, the mama-to-be has a great support system behind her!