Naomi Watts and Ex Liev Schreiber Celebrate Son Sasha's 16th Birthday with Rare Photos: 'So Lucky'

The actress shares her two kids — Kai and Sasha — with ex Liev Schreiber

Naomi Watts and ex Liev Schreiber are celebrating their "darling boy" on a milestone birthday.

On Tuesday, the Goodnight Mommy actress, 54, posted a sweet tribute to her Instagram to her son Sasha as he turned 16. Sharing a series of rare photos with her son over the years, Watts wrote, "Happy 16th to my darling boy."

"I cannot believe how fast this happened?! Beyond proud of the young man you've become with the most wonderful spirit, fantastic sense of humor and kind, compassionate soul."

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Related: Liev Schreiber Steps Out with Pregnant Girlfriend and Son Sasha in Rare Appearance at Screening

"So lucky I get to be your mum," Watts wrote. "Thank you for still letting me hold your hand sometimes. Even though I know you probably just forget to pull it away. You blow me away!! 🤦‍♀️Happy birthday to ❤️🎂🎉 @sashapeteschreiber."

Several of Watts' famous friends chimed in with birthday wishes in the comments, including Julianne Moore, Gwyneth Paltrow, Andy Cohen, and Julianna Margulies among others.

Watts shares her two kids — Sasha and Kai, 14 — with Schreiber, who also shared a birthday tribute to Sasha on his Instagram page.

"Happy Birthday Handsome!" Schreiber wrote alongside a close-up shot of the father-son duo.

In late June, Sasha was seen out with his dad while attending a screening for Schreiber's new limited series on National Geographic, A Small Light. While at the event, Schreiber and his son were joined by his pregnant wife Taylor Neisen, 30.

In the photo, Sasha stood to his dad's left and wore a tie-dye sweatshirt and white pants, while Neisen wore a form-fitting black dress that highlighted her baby bump.

Earlier this year, Schreiber and Sasha went on a father-son trip to Nassau, where the teenager officially became a certified diver. The actor sat poolside, played mini golf with Sasha and swam in Stuart's Cove. On Instagram, Schreiber shared photos of their trip as well as Sasha getting certified.

"So proud… Like a fish," he wrote alongside photos of Sasha scuba diving.

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