How 'Cobra Kai' stars Tanner Buchanan and Mary Mouser kept romance secret before surprise engagement

LOS ANGELES, CALIFORNIA: ‘Tis the season of love, and Tanner Buchanan, 26, and Mary Mouser, 28, are the latest couple to join the growing list of engaged stars.

After years of fans shipping them together, followers of Netflix’s 'Cobra Kai' can finally rejoice as their brief onscreen romance has transformed from reel to real life. 

Buchanan and Mouser, who portray Robbie Keene and Samantha LaRusso in the 'Karate Kid' spinoff series, surprised fans by announcing their engagement just before Valentine’s Day. While their characters shared a short-lived romance in Season 2, it didn’t work out in the show - but reality had other plans.

Tanner Buchanan and Mary Mouser are engaged

The couple made their red carpet debut as an engaged pair at the 'Cobra Kai' series finale premiere on February 12, 2025, at The Egyptian Theatre in Hollywood. While their presence was expected, what caught everyone off guard was their big reveal.

Beaming with joy, Buchanan and Mouser proudly displayed their engagement rings, leaving no room for doubt. The much-in-love couple even shared an affectionate kiss on the red carpet after posing with their bejeweled left hands.

Shortly after, the duo took to Instagram to make their engagement official. Sharing a carousel of romantic photos, they captioned the post, “We’re so happy to finally share that we’re engaged.”

“This is such a special moment in our lives, the closing of one chapter and celebrating the continuation of another,” added the couple, before continuing, “We’re so grateful for the love and support, and though we’re partial to having our private moments, we’re excited to share this check-in to our world."

When did Tanner Buchanan and Mary Mouser’s relationship start?

True to their statement about valuing privacy, Tanner Buchanan and Mary Mouser had kept their romance under wraps. While the 'Cobra Kai' fandom has long speculated about their relationship, fans only recently got confirmation as the hit martial arts series nears the end of its sixth and final season.

Though their public announcement came in 2025, speculation about their relationship had been brewing for over a year.

While the exact date of the commencement of their relationship is not known, one can surely tell that their friendship blossomed in 2018 when they started sharing the screen in ‘Cobra Cai’.

Nevertheless, as Perez Hilton reported, their relationship did not start instantly, as the ‘Frenemies’ actress was dating her then-boyfriend, Brett Pierce, during that time. 

In fact, in 2020, she also penned a fifth-anniversary tribute when she wrote in the since-deleted post, “Five years with you has felt like five minutes. Happy anniversary to the most spectacular boyfriend – who I am so grateful to say is also my best friend, my whole heart, and the only one I would want to be locked in a cabin with for the whole weekend.”

In 2021, she also revealed to Kelly Clarkson that it was Pierce who encouraged her to take up the ‘Cobra Kai’ role as he was a huge ‘Karate Kid’ fan. Nevertheless, the former couple’s relationship ran its course. 

Meanwhile, the now-engaged pair have remained friends throughout their time as stars of the young-adult drama.

Mary Mouser wished ‘Happy Birthday’ to her ‘bestie’ Tanner Buchanan in 2019

In 2019, Mary Mouser posted a long note wishing her co-star on his 21st birthday. 

Taking to her Instagram, the Arkansas native wrote, "HAPPY BIRTHDAY TANNER BUCHANANANANANANANAN! i know most normal people would post for your birthday at midnight the morning OF your bday - but we’re not normal besties. So here I am. you are the most kind and beautiful soul of all time, I am so grateful to know you and adore you!"

She further added that she couldn’t “wait to celebrate” with him, citing, “for this birthday and all the other made up holidays that we create just so we can party together!”

“You’re the greatest and you deserve the greatest! thank you with all my heart for everything bestest budddddddy! (even for the times where you get on my last freakin nerve!) Now flip through and enjoy the many faces of @tannerbuchananofficial 🖤,” gushed the ‘Son of the Mask’ actress. 

She was also her "bestie's" greatest cheerleader when he starred in the film 'He's All That'. Hyping up her best friend, she wrote in an Instagram post, "GO WATCH MY BEST FRIEND FREAKING KILL IT IN @hesallthatmovie!!!," before adding, "v v proud bestie right here 💖."

Tanner Buchanan revealed romancing Mary Mouser on screen gave him 'anxiety'

While the co-stars-turned-lovers had to play the role of a couple in the second season of the show, Tanner Buchanan shared that it gave him cold feet. 

Speaking to Interview Magazine, the 'He’s All That' actor shared that filming the romantic scenes with Mouser gave him “the most anxiety.”

He continued, as reported by People, “You could talk to Mary [Mouser] about this because she and I are such good friends,” before adding, “When we had our first kiss scene in season two, they were asking us, ‘Are you ready?’ My heart was pounding, I was shaking. It just feels weird to go to that place, because we’re such good friends.”

Tanner Buchanan and Mary Mouser's shared love for Disneyland and Taylor Swift

The now-engaged couple's diaries were full of eclectic memories as they visited Disneyland together in 2022. After visiting California Disneyland in November 2022, they went to Disneyland in Paris, France the next month. 

They also posted cuddling up in cozy Disney merchandise as they were frolicking through the parks. 

In 2023, the couple also attended Taylor Swift's Eras Tour concert in Atlanta in April, as photos of the duo posing for pictures with a fan went viral.

Showrunners celebrate Tanner Buchanan and Mary Mouser's engagement

As the news of the couple's engagement became public, Netflix, along with the show's creator celebrated the news with delightful posts on social media. 

Netflix celebrated their engagement by sharing a photo of the couple, writing, "COBRA CRYING BECAUSE TANNER BUCHANAN & MARY MOUSER ARE ENGAGED."

Soon, the showrunner John Hurwitz joined the conversation, as he wrote, "We’re matchmakers first, showrunners second. Our primary goal with Cobra Kai was for Daniel LaRusso’s daughter and Johnny Lawrence’s son to fall in love in real life. Mission accomplished. So happy for them! A perfect couple! #CobraKai #TrueLove."