Kate Hudson and son Ryder.Photo:Kate Hudson/Instagram

Kate Hudson and son Ryder

Kate Hudson/Instagram

The actress, 44, tells PEOPLE in an exclusive conversation how she is in disbelief that her oldest child, sonRyder, is no longer a teenager, and how she was only “a couple years older” than him when she became a mom.

“That’s been the wild discovery for me,” theGlass Onion: A Knives Out Mysterystar says. “I just can’t believe that I was only a couple years older than him when I decided to have a child.”

“The fact that we’ve been able to get through it together like this, and really, honestly, grow up together, has been incredible,” Hudson adds of herself and son Ryder, 20, whom she shares with ex-husbandChris Robinson.

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Kate Hudson with her three kids.Kate Hudson/ Instagram

Kate Hudson with kids

Kate Hudson/ Instagram

Looking back, Hudson says she’s amazed it’s been two decades since she welcomed her first child. (She also shares daughterRani Rose, 5, with fiancéDanny Fujikawaand sonBingham “Bing” Hawn, 12, with ex-fiancéMatt Bellamy.)

“I guess while raising him, [I was] just in it and present, and then they fly the nest, and they’re sort of cooked — and they’re adults!” she says. “You look back going, ‘Wow, I can’t believe [it].’ "

And while Hudson — who recently partnered withRakuten— says Ryder is “so wonderful,” “in a great place” and “enjoying his life,” there is one thing that does bother her about him now being an adult.

“I wish he lived a little closer,” she admits. “But I just love seeing him explore his adulthood. He’s an adult, you know? He’s out in the world and doing his thing. … We’re very close and I’m very proud.”

Kate Hudson and her three kids.Kate Hudson/Instagram

Kate Hudson and her kids

Hudsoncelebrated Ryder’s 20th birthdaylast month, sharing a photo on Instagram of a birthday cake featuring numerical candles for “20,” plus white frosting with dark chocolate sprinkles.

“I’m gonna have to let this one digest for a bit..: 😭 My beautiful boy, happy 20th,” the proud momwrotein her caption. “I love you beyond @mr.ryderrobinson ✨.”

source: people.com