Mary Mouser: Biography, Health, Black Belt & Relationships

If you’ve watched Cobra Kai and wondered about the actress behind Samantha LaRusso, you’re not alone. Mary Mouser’s life off-screen — from her real martial arts skills to her Type 1 diabetes advocacy — is just as compelling as her character’s karate battles. This guide separates verified facts from common myths, using official sources and her own public statements.

Born: May 9, 1996 ·
Birthplace: Pine Bluff, Arkansas, USA ·
Known for: Role of Samantha LaRusso in Cobra Kai ·
Instagram followers: 3 million ·
Martial art rank: Black belt in Shorin Ryu Shorinkan (promoted 2021)

Six key facts about Mary Mouser, drawn from verified records:

Are Mary Mouser and Tanner Buchanan a couple?

Engagement announcement

Mary Mouser and Tanner Buchanan, who play love interests in Cobra Kai, confirmed their real-life engagement in 2023. Multiple credible sources, including E! News (entertainment news outlet), reported the news. They are not yet married as of the latest updates.

On-screen relationship vs. real life

Their characters Samantha LaRusso and Robby Keene have a complicated on-again, off-again romance. Off-screen, the actors are a real couple — engaged, not just co-stars. This distinction is often blurred in fan discussions.

Tanner Buchanan’s partner

Tanner Buchanan’s fiancée is Mary Mouser. There is no evidence of other relationships for Buchanan since the engagement became public. The couple has not publicly shared wedding dates.

The engagement clarifies the real-life relationship for fans.

What is Mary Mouser diagnosed with?

Type 1 diabetes diagnosis

Mary Mouser has Type 1 diabetes, a condition she disclosed publicly in 2022. She told Healthline (health journalism site) that she was diagnosed at age 13, shortly after her birthday. She experienced symptoms for about six weeks before diagnosis, including thirst, headaches, irritability, and frequent urination.

Public disclosure and advocacy

Since then, Mouser has used her platform to raise awareness. She participates in JDRF walks and events (diabetes research organization) and has spoken openly about the emotional challenges. Business Insider quoted her saying self-love is “an active daily choice, like brushing your teeth or taking a vitamin.”

Impact on her life and career

Managing diabetes while performing martial arts choreography for Cobra Kai requires constant vigilance. In a Tandem Diabetes profile (insulin pump manufacturer), she described wearing an insulin pump for nine years (as of 2023) and balancing blood sugar during physically demanding shoots.

“Diabetes is a major part of my life and my confidence journey,” Mouser told Business Insider (financial news publication).

— Mary Mouser

Mouser’s advocacy makes her a role model for those with similar conditions.

Does Mary Mouser have a black belt in real life?

Shorin Ryu Shorinkan promotion

Yes, Mouser earned her black belt in Shorin Ryu Shorinkan in 2021. The promotion was announced on Facebook by Franz, her sensei. This is a verified primary source, not a fan assumption.

Training for Cobra Kai

She trained specifically for the role, learning karate choreography from the show’s stunt team. She was not a lifelong martial artist before the series. The black belt reflects dedicated practice alongside her co-stars.

Previous martial arts experience

Before Cobra Kai, Mouser had no documented martial arts background. Her black belt is the result of years of training for the series, which demands extensive physical choreography.

Her martial arts training demonstrates discipline and commitment.

Why did Mary Mouser gain weight?

Weight fluctuation due to diabetes

No official statement from Mary Mouser explains any weight changes. Type 1 diabetes can cause fluctuations in body weight due to insulin therapy, but Mouser has not attributed any specific change to her condition.

No official statement on weight gain

Internet speculation about weight gain is unsubstantiated. Mouser has never addressed the topic publicly. Fans online have theorized about diabetes medication or lifestyle changes, but these remain theories.

Body positivity and fan speculation

Mouser’s advocacy emphasizes confidence and self-love, not weight. She has encouraged fans to focus on health rather than appearance.

Speculation without evidence should be ignored.

Did Xolo Mariduena and Mary Mouser date?

Rumors on set

Fans have long speculated about a relationship between Mouser and Xolo Mariduena (Miguel on Cobra Kai). No verifiable evidence supports this rumor. Their on-screen chemistry as characters may have sparked the assumption.

Relationship status of Xolo Mariduena

Mariduena has been publicly linked to other people, but not Mary Mouser. Neither actor has ever confirmed a romantic connection.

Clarification from official sources

No credible source — interviews, social media, or tabloids — has substantiated the dating rumor. The claim appears only in fan circles and gossip aggregators.

On-screen chemistry does not imply off-screen romance.

Quotes from Mary Mouser and those close to her

“The most important thing I can do is make sure I’m taking care of myself — and if that means checking my blood sugar before a fight scene, then that’s what I do.”

— Mary Mouser, interview with Healthline

“Self-love is an active daily choice, like brushing your teeth or taking a vitamin. You have to choose it every day.”

— Mary Mouser, quoted in Business Insider

“Mary worked incredibly hard to earn her black belt. She trained consistently for years to achieve that level.”

— Franz, sensei (Facebook announcement, 2021)

For readers following Mary Mouser’s journey, the verified facts provide clear answers to the most common questions. Diabetes hasn’t slowed her career; her black belt is real but earned through on-set dedication; and the engagement to Tanner Buchanan is genuine. The one pattern that emerges is an actress who takes ownership of her story — whether through health advocacy, martial arts discipline, or setting the record straight on rumors. For fans, the takeaway is clear: Mary Mouser’s story is defined by verified facts, not rumors.

Fans interested in more about Mary Mousers health and relationship details can find a comprehensive overview of her personal life and medical journey.

Frequently asked questions