Former AFL player Daniel Stewart’s loved ones have mourned “what should have been” on his birthday, just a week after his sudden death.

Stewart, who played 36 games for Port Adelaide before building the Body Fit Training (BFT) fitness empire with ex-teammate Matt Thomas and friend Cam Falloon, died aged 37 last Friday.

The man better known as Snowy would have turned 38 this Friday.

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Stewart’s wife Laura reposted footage from their oldest son Bernie’s third birthday to her Instagram.

“Happy birthday daddy,” she wrote.

“We love and miss you more than words can describe.”

Port Adelaide announced Stewart’s death last week, sparking an outpouring of grief from the AFL and fitness communities.

BFT confirmed he had suffered a sudden health episode with Laura adding in a tribute that her husband had “a heart too big for this world”.

Thomas and Falloon shared extended tributes with a collection of photos on Stewart’s birthday on Friday.

Daniel Stewart played for Port Adelaide before turning to the fitness industry. Credit: Port Adelaide

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“Dear Snowy, it’s hard to comprehend what should have been,” Thomas wrote.

“Today is your birthday and to know you’re not here is something I still can’t come to terms with.

“17 years of friendship, brotherhood, building businesses and sharing life together. I don’t think anything could ever prepare me for having to say goodbye to my best mate.

“We’ve achieved so much together, but the hardest part is knowing how much we still had ahead of us. More adventures, more family holidays, watching our kids grow up, more firsts, more milestones and so many more memories we were supposed to make together.

“Today should have been another birthday celebrated together, another year of memories and another excuse to remind you how much you mean to me.

“Happy birthday, Snowy. You’ll always be 37, and I’ll always miss you more than words will ever explain.”

Falloon said he had been saving his “first ever Instagram post for something or someone special” but “never imagined it would be for this”.

“There’s no one more fitting to dedicate my first post to than Snowy,” he wrote.

Falloon said he was “devastated, absolutely heartbroken”.

“I’ve started writing this a hundred times through teary eyes. How do you put 18 years of friendship, loyalty and admiration into words?” he began.

“Snowy, I met you as a 20-year-old kid walking into Port Adelaide. I was your high performance manager and strength and conditioning coach.

“You were a talented, tall, skinny kid with a huge smile and plenty of work to do.

“Four years of guiding you and pushing you as an athlete. Memories of your first game and running 150s at Santos on a Tuesday morning in pre-season. A sight to behold!

“18 years later, you’re one of the most significant people in my life. I’m so grateful.

“Whether over coffees, red wine or a whiskey, we shared so many laughs and tears.

“I cherished our training sessions and took so much joy from your success, in sport, business and life.

“Your ability to always see the positive in life and in people was something special.

“We caught up recently, and you thanked me for the journey we’d been on. Mate, it is you I thank.

“Beyond the business, you taught me so much. I’ll forever be grateful for those lessons.”

Falloon recalled Stewart and Thomas ‘taking a punt’ on him to open their first BFT in Prahran before building a “deep trust and belief in each other” over the next 11 years.

He said the business “isn’t why the world lost something this week”.

“You are one of THE great human beings,” Falloon write.

“A beautiful man. Genuine. A huge smile and a heart of gold. Time for everyone. A real connecter. A people person.

“The passion and genuine care you and Matty brought every day to your staff and members built and sustained your businesses.

“What most people work on every day came effortlessly to you. It’s who you are.”

Falloon vowed to ensure Stewart remains “a significant part” of his and his family’s lives, in part through Laura, Bernie and youngest son Lando.

“Fit, young, with so much life ahead of you. It doesn’t make sense. I’m devastated and finding it hard to reconcile.”

Falloon said Stewart was “left without life insurance” and the family home is now “at risk”, asking for donations to support the family.

“Happy birthday, mate. I miss ya,” he said.