Don't worry, you're not seeing double.

Although Reese Witherspoon has proven that she has yet another mini me with son Tennessee. The Legally Blonde star shared a sweet snap of her youngest—whom she shares with ex Jim Toth—in honor of Tennessee's birthday. And it is clear he gets his bright blonde locks from his mom. 

"Happy 12th Birthday to my wonderful son, Tenn!" Reese wrote on Instagram Sept. 27, alongside a photo of the two. "I'm so lucky to have your joyful, curious, hilarious spirit in my life making me laugh everyday. I love you, buddy."

And Reese wasn't the only one wishing him a happy birthday, as his siblings Ava Phillippe, 25, and Deacon Phillippe, 20—their dad is Ryan Phillippe—also gave a shout out to their little brother.

"Can't believe my once tiny brother…" Ava shared on her Instagram Stories Sept. 26 with a throwback photo of the two, per People, "... is now 12 years old & about to be my same height."

The second image featured a recent photo of the pair, with Tennessee standing just a few inches shorter than Ava.

"Happy happy birthday to this quick-witted, funny, curious & thoughtful dude," she added, "that I'm lucky enough to call my baby brother."

Deacon shared his own message to his Instagram Stories, writing, "What up 12," according to People and adding, "Love this kid."

And while the siblings have a large age gap, Reese has spoken before about how having that time between her children was actually something she appreciated.

"I had kids when I was 23," the 48-year-old told E! News in 2023, "so I think I always worried, 'Am I doing this right? Am I messed up? Did I do it right?'"

She added, "But now, I feel more confident—I've been doing it for 23 years—that I probably got some stuff right."

Another thing she got right? Making sure all of her kids look exactly like her. So much so that sometimes people think she's Ava.

"I love being mistaken for her because it makes me feel so young," she said to InStyle in 2021, noting Ava doesn't seem to mind it either. "She really rolls with it. I'm sure it's not easy looking exactly like your mother."

Curious about other celebrity parents and their mini me kids? Keep reading.

The Full House alum appears with her look-alike eldest daughter (left) and daughter Beatrix during a trip to Jamaica in 2023.

Like mother like daughter. After becoming a household name on The Real Housewives of Beverly Hills, the former supermodel Yolanda Hadid's daughter Gigi Hadid broke into the fashion industry as a teen and has been rocking runways ever since.

Clint Eastwood's fifth child, son Scott Eastwood, has followed in his movie star footsteps by starring in films like Suicide Squad, Snowden, The Fate of the Furious and Pacific Rim.

The Bon Jovi singer and his third child is his mini-me. Pictured: The two appear on either sides of with the musician's wife, Dorothea Bongiovi, and their youngest son Romeo Bongiovi at the Jefferson Awards Foundation' 2017 DC National Ceremony at the Capital Hilton in Washington, DC. in 2017.

The look-alike duo is all smiles while attending a 2016 performance of Finding Neverland in the Big Apple. 

Woah, the Marsden men's resemblance was uncanny at the 2017 SAG Awards.

Double take! The Real Housewives of Atlanta alum's  daughter looks like her younger sister!

The soccer star has the cutest plus-one ever at the London premiere of Ronaldo.

Sailor is taking after her mom in the modeling industry.

And Kate's daughter is also following in her mom's famous footsteps.

Here posing for an Instagram snap before the Hot Pursuit premiere in Los Angeles, mom and her daughter have never looked more alike!

Like mother, like daughter. The two attend the Vanity Fair Oscars party in 2015.

With their matching jumpsuits, sleek hair and glasses, the two look more like twins than mother and daughter! "That moment when you realize you actually are becoming your mother #twinning #imnotmad," Willis joked on Instagram.

Pictured here in 2010, the pop icon's daughter is a fashionista just like her mama!

You'll get a kick out of how much the soccer star and his son look alike.

The spunky morning show host celebrated her daughter's 14th birthday with this adorable pic. Look at that resemblance!

Once upon a time in Hollywood...the Kill Bill actress twinned with her daughter on the red carpet.

Little Blue stole the show at the 2017 Grammys, and she's totally #twinning with her pops!

The Days of Our Lives star and her daughter get in the holiday spirit at Disney On Ice Presents Frozen at the Staples Center. 

The mother-daughter pair looked like virtual twinsies (especially with those matching bobs) at the Chanel fall-winter Haute Couture show in Paris.

The Oscar-winner and her daughter both rock the red hair.

The nearly identical stunning stars even dress the same!

The Fuller House star and her daughter are practically twins at the Summer TCA Press Tour. 

The Last of the Mohicans and Lincoln star's young adult son, whose mother is French actress Isabelle Adjani, made his big runway debut at 2015 Paris Fashion Week, walking into the Chanel show with Julianne Moore.

The two stunned on the red carpet at the Olivier Awards in London.

If you didn't know better, you might've guessed they were sisters!

This apple certainly doesn't fall far from the tree!

Mammia Mia! You can certainly see the family resemblance.

The EGOT winner posted this baby photo of himself, looking exactly like baby Luna on Oct. 6, 2017

This mother-daughter duo never fails to turn heads.

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