Naomi Watts Celebrates 'Darling' Kai's 13th Birthday: 'You Shine the Brightest Light'

Naomi Watts' youngest child is now a teenager!

The Gypsy actress, 53, celebrated Kai's 13th birthday on Instagram Monday with a solo shot of the teen. "My darling Kai, 13 today!! Whaaat?!?" Watts captioned the post. "You shine the brightest light, from the depth of your soul, we feel it. Thank you for choosing me as your mummy. I'm beyond proud of you."

She added, "Happy birthday baby (baby foreva! 🙏) we celebrate your mind, your talent, your wit and your incredible courage today and every day. 💕 😇."

In November 2020, Naomi — who shares Kai and Sasha, 14, with ex Liev Schreiber — shared her experience with juggling motherhood and self-care during the COVID-19 pandemic.

"Mommy does embarrassing dances with the children," Watts joked, possibly referencing a TikTok dance she and Kai did together in April of that year, and another she and Schreiber performed with their two children the following May.

"Sometimes you feel like you're a supermom — baking [a] cake, playing board games and teaching them how to use the vacuum cleaner; you're just fully on top of it," she continued. "And other times, you're like, 'Oh God, just let me hand them the devices and let me get done what I need to do,' you know?"

"That's just the reality, and you have to forgive yourself on the days that you need to take that time for yourself and create that space," Watts added.

She described 2020 as a "constant ride on [one's] nervous system," with "anxiety levels" that "are through the roof."

"There's been beautiful, simple moments with the family dotted in there. And then really hard times with the kids not quite understanding," she explained. "You know, my kids are at the age where you don't want them to be sitting in front of the news and absorbing all the dark, ugly facts of everything, but they're too old to hide everything."

"But they get frustrated," Watts said. "So it's a tough thing for everyone to navigate. But you just find your way along. And there are good days and bad days."

Back in 2018, Schreiber opened up about his co-parenting relationship with Watts after they announced their separation in 2016.

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"It's always hard, you know? You build a life with someone and things change," he said on Sunday Today with Willie Geist at the time. "And I think the way that we've looked at it is that we'll always be partners with these kids."

"It's important to support each other," added Schreiber. "I was making some jokes at breakfast about Mommy with [the kids] and their eyes light up when I talk about her. You can see how important it is to them that their parents care about each other."