The couple, who welcomed twins Alexander and Ella on June 6, enlisted the help of celebrity-loved childcare expert Connie Simpson, who spoke to PEOPLE for this week’s issue about the famous family ahead of the release of her new book The Nanny Connie Way.
“It was really funny because the little girl was such the essence of her mother and the little boy is the essence of his dad,” says Simpson, who has helped other celebrity couples like John Krasinksi and Emily Blunt and Justin Timberlake and Jessica Biel.
“It just kind of grew … you could see it manifesting every day that you were with them,” she adds. “The look that George has in his movies, his son was showing that too and I just thought that was the cutest thing. They’re all cute together.”
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Of Ella, Simpson reveals to PEOPLE, “She just has that daintiness and that beautiful glow like Amal has and it was really funny to see the kids take on the personality of their parents.”
“The goofiness that you see in George in his movies, that little gooey look in those eyes,” she explains of how baby Alexander resembles his dad. “It was amazing because once again — family.”
Simpson explains that she “came out of retirement” to help the Clooneys, and that the experience of taking care of two babies at once inspired her in her work even further.
“Working with twins, it made me come up with a saying — chess not checkers,” she says. “Because you have to stay three moves out, and no two babies are alike. If you have a girl/boy situation, you’re going to be knee deep in learning about the two different sexes right off the bat. And that’s different. But it’s a blessing.”
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Amal, 40, recently gave Vogue a glimpse into the couple’s new life as parents of two, posing for the publication’s May cover story and revealing the twins have said their first words.
“We’ve had some ‘Mamas’ and ‘Dadas,’ ” shared the human rights lawyer, adding of her 56-year-old actor husband, “George was very careful to ensure that ‘Mama’ was the first word.”
The Nanny Connie Way: Secrets to Mastering the First Four Months of Parenthood is available now on amazon.com.
For much more from Nanny Connie Simpson, pick up the latest issue of PEOPLE, on newsstands Friday.