Tom Hanks and Rita Wilson may be two of the most prominent faces in Hollywood — but did you know they're also some of the best grandparents around?

"We’re the cool grandparents," Rita, 60, recently confessed. And her actor hubby Tom, also 60, agreed. "The most cool!" he said.

The couple — who married in 1988 — have three grandchildren, and they all call Tom and Rita "pappou" and "yia yia" in Greek tradition. Tom's son and Rita's stepson, Colin, 39, has two daughters, Olivia, 6, and Charlotte, 3, and the duo's son Chet, 26, also has a daughter, who will turn one-year-old in April. Tom is also a dad to Elizabeth, 34, from a previous marriage, and Tom and Rita additionally have a younger son together, Truman, 21.

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Tom and Rita in February 2015.

An insider exclusively revealed to Closer Weekly that Tom and Rita "especially delight when they have alone time with the girls." And they have a blast when they do! "Tom’s a kid at heart and thrives on playing chase or portraying a funny monster to his granddaughters, and Rita sings and dances with them," the source added.

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Tom has also joked that their grandkids "just put up with us." However, he and Rita call their treasured time with them, "parenthood fantasy camp: You have all the fun without any of the long nights." Too funny!

Tom additionally shared his love for children! "I’m a sappy guy," the Sully star has admitted in the past. "There’s nothing I’d rather be doing than having that little kid on my knee or in my arms."

While Tom isn't busy being the world's best grandfather, he's working on his new book! The Big actor is writing his first-ever book, which will be titled Uncommon Type: Some Stories. The publication will include 17 short works of fiction and is set to come out in October 2017.

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He has been working on the piece since 2015. "I wrote during press tours [and] on vacation," he previously revealed. “I wrote on planes, at home, and in the office." We can hardly wait to read it!

For more on Tom and Rita, pick up the latest issue of Closer Weekly, on newsstands now!

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