Sarah Michelle Gellar and Reese Witherspoon's kids are besties.

Cruel Intentions was one of the most iconic movies of the ’90s, and it helped make Sarah Michelle Gellar and Reese Witherspoon household names. Now, it turns out that the co-stars’ toddler sons are the best of friends.

Too cute.

Gellar and Witherspoon have kept in touch ever since they worked on the 1999 movie along with Selma Blair, Joshua Jackson and Witherspoon’s ex-husband, Ryan Phillippe.

They've been besties since 1999.

Gellar recently told Entertainment Tonight that her son Rocky and Witherspoon's son Tennessee, who are both three years old, are pals and even car pool together.

"Reese's son and my son are best friends," she said.

Gellar, 38, also added that she was surprised by how much time had passed since the teen movie was released after it was revealed that Cruel Intentions was being made into a musical.

Sarah Michelle Gellar with her kids, Rocky and Charlotte. Image via @sarahmgellar Instagram.

"We all see each other, so you don't realise you're getting older. Then all of the sudden you're faced with the revival of your movie, with all these young kids in it, and were like, 'Oh, we're old.' That's when it hits you," Gellar said.

It happens to the best of us, Sarah Michelle...

Gellar has been married to her I Know What You Did Last Summer co-star Freddie Prinze Jnr since 2002 and they also have a daughter, six-year-old Charlotte.

Reese and Tennessee. Image via @reesewitherspoon Instagram.

Witherspoon has two kids with Phillippe - Ava, 16, and Deacon, 12. She married Jim Toth in 2011 and she gave birth to Tennessee in 2012.

We can't imagine how cute Tennessee and Rocky's playdates are...

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