February 3, 2016 10:33 AM EST

Buffalo Bills player Tony Steward revealed Tuesday that his fiancée has died after battling cancer at the age of 26.

In a heartfelt and emotional Instagram post, the linebacker paid tribute to his bride-to-be Brittany Burns, a former Clemson rower.

“Brittany Ann Steward! Wow BEAUTIFUL is the only way I know you,” he captioned a photo of Burns. “You have the biggest heart I have ever seen in my entire life and I promise you that it will live on in me, our family and every single soul you have touched.

According to Syracuse.com Burns was diagnosed with a rare form of ovarian cancer on Dec. 9.

Steward’s post added: “You are the strongest and most loving soul to step foot in this world. You have been my rock, my motivation, my heart, my soulmate, my everything since the day I laid eyes on you.”

The couple got engaged in December – which they documented on social media – shortly after Burns was diagnosed with cancer.

Following Burns’ diagnosis, the couple started a fundraiser called “Britt and Tony’s Fight Like a Girl Campaign,” in an effort to help “other women who are battling ovarian cancer.”

As of Wednesday, the campaign has raised $6,757.

“Every single day of your life you have been a fighter and I know this because of the unbelievable family you brought me into,” Steward continued in his post. “We will all honor everything you stand for in life. I will continue to be the person that you always bring out in me. Believe me when I say that I deeply love you with every ounce of everything in me. Love always, Your Fiancé #fightinglikeagiril #fightlikebritt”

A press release from the Buffalo Bills also offered the team’s condolences, remembering Burns as “an active member in the community through the Buffalo Bills Women’s Association.”

Steward was drafted to the Bills in the sixth-round in 2015, Syracuse.comreports. He finished the season on injured reserve.

A little over a week before Steward announced her death, Burns took to her Twitter to post a hopeful message.

“Thankful for the care at the hospital but I’m so ready to move on and start doing better from home,” she tweeted.

Another Twitter post suggests that she was being treated at the Hospital of the University of Pennsylvania.

In January, the 26-year-old posted a photo collage to her Instagram account, highlighting the “great moments” of 2015.

“I’ve got to beat the only news that brought 2015 down, cancer,” she wrote in the photo’s caption.

The collage featured five photos, several of which showed Burns with Steward – one shows the football player proposing to Burns.

In another, Burns is seen laying in a hospital bed with a stuffed teddy bear.

This article originally appeared on People.com

Contact us at editors@time.com.

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