The Big Little Lies actress, 44, shared a very sweet photo with her 17-year-old on Instagram Stories and they look more like brother and sister than mum and child.
Reese was in the passenger seat of her car with Deacon at the wheel in the photo and she captioned it: "When I'm tired, Deacon always offers to drive me."
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She was wearing a hoodie and sunglasses in the photo, while Deacon concentrated on the road.
The apple doesn't fall far from the tree as he sports the same chiseled jawline as his A-list mum and the resemblance is uncanny.
Reese is also a mum to Ava, 21, and Tennessee, eight. She shares her oldest children with her ex-husband, Ryan Phillippe, and her youngest with her husband, Jim Toth.
Deacon dotes on his mum
She is a master at juggling a successful career and motherhood but recently revealed on The Drew Barrymore Show that in the early days she struggled to keep all the plates spinning.
"I got pregnant when I was 22 years old," she said. "And I didn't know how to balance work and motherhood. You just do it, you know?
"I'd made movies but I hadn't established myself as someone who could demand that it shoot close to my kids' school or, you know, I didn't have any real power, leverage within my industry.
Reese shares her two oldest children with Ryan Phillippe
"I was just like every other mum trying to figure it out - and dad out there, and partner, and grandparent who's raising a child."
But she says being a mum is worth every single sacrifice she's ever had to make.
"You take the food out of your mouth, the clothes off your back, the sleep out of your life," she added.
"But every bit of it - every bit of that sacrifice is truly worth it because you feel like, that's what makes me wake up on a Sunday. It's not movies or my job, it's my kids."
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