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Meet Marie

Born in Washington D.C. in 1990, I began to ride horses when I was just a little girl. When my parents moved our family back to Bordeaux, France, I began to train seriously all while pursuing a bachelor’s degree in Business Administration and Equestrian training. 
In 2008, Marie was National Champion winning a Gold Medal at the Amateur Grand Prix 3 Days Eventing Olympic Discipline. 

In 2013, back in the USA, I got my first professional job in the equestrian world. The President of Studbook Selle Français North America hired me in Lexington, Kentucky to promote and show young Selle Francais horses, a significant accomplishment, testament to my talent and test of my skills. Eight months later I moved to Wellington, Florida to ride professionally for Alison Firestone until the accident happened

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By the time I was 18 years old, I had already won a gold medal for France and was selected to attend SAMUR, the prestigious national riding school. Life was busy but I was living my dream! 

Marie Vonderheyden

On the morning of February 20, 2015 after a typical ride cooling down my horse, I was found on the ground knocked unconscious. Rushed to the hospital already in a coma, I had sustained severe traumatic brain injuries (TBI). After multiple brain surgeries to try to save my life, the doctors were not sure I would ever wake up.

Eventually, I did wake up, unable to speak, swallow or move the entire right side of my body, which was paralyzed. The majority of my memory had also been erased.

After months in the ICU, I was transferred to the Shepherd Center for Spinal Cord and Brain Injury Rehabilitation in Atlanta. With several more surgeries and intensive therapies I began to improve, slowly but surely, I was getting a second chance at life.

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Then my life changed forever...

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 “At first she couldn’t even open her mouth or speak or move. Marie didn’t know where she was. So we focused on the immediate next step, saying a few words, then a few sentences, and responding to basic questions.”

Cecile Vonderheyden, Marie's mother

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Unfortunately, seizures are a part of our new reality, and we navigate around how much my brain permits. But I never give up.

Once I acquired enough strength to stand on my legs and put one foot in front of the other, it was time to start hippotherapy and therapeutic riding.

“Marie’s TBI affected her physically, mentally and emotionally. Her right side was more affected and her trunk and neck control were weak. Some of the biggest challenges were her mental-emotional state and being able to cope and work through her frustrations."

Now, back to life...

"Marie is extremely goal-oriented, so I wanted to help her focus on her goals and facilitate reaching them.”

Kelcy Rainer, PATH Intl. Advanced Certified Instructor 

Therapeutic Program Director , Chastain Horse Park Atlanta

Fortunately, as a former professional equestrian, I maintained an impressive amount of muscle memory. I progressed quickly from needing a lot of assistance to independent riding. Today I am a Para-Equestrian Athlete on Team USA, training and competing to qualify for the 2024 Paralympic Games in Paris. Also, I love Ralph Lauren fashion and hope to one day be the face of his adaptive clothing line!

My family and medical team have been amazed by the countless benchmarks I have reached. Each day presents new marvels and wonders in my development. Together with my mom, we tackle each day with as much therapy as my body and mind allow.


Doctors say the human brain can continue to heal 10-15 years after an injury. It’s only been five years since the accident and my back to life story began.

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