A 5-year-old boy — who was an avid Spider-Man fan and described as a “loving pure soul” — died suddenly while on a sleepover at his friend’s house. 

Jagger Wing was found unresponsive at a family friend’s parents’ home in Newburgh, Indiana, on May 30 — before he died in a hospital, his devastated family revealed in an obituary.

Mystery still surrounds the boy’s death. His mom, Alex, 29, revealed the family has a history of underlying heart conditions, but doctors are still probing why the tragedy happened. 

Alex revealed her son, who started wrestling from the age of 4, was playing with his pal — hours before he was found unresponsive.

“He had played hard outside,” she told WCTV.

“He was with his friends. He was staying the night at a friend’s house when it happened. My best friend of 17 years and I can’t imagine that feeling and situation. I hate that I wasn’t there.”

Jagger, described by family friends as “a beautiful, energetic, loving, caring, and pure soul,” had a passion for Spider-Man and was due to start kindergarten in August.

“He just learned how to ride a bike. He loved to be active. He loved to question everything we were doing,” Alex said.

His dad, Damon, 31, revealed his son wanted to replicate the wrestling moves he had seen on TV.

“He wanted to wrestle,” he said.

“There was no sitting on your butt. He wanted to try for a double leg. He watched every UFC fight with me.

“He just loved the game.”

Despite his love for sports, the energetic 5-year-old, who had an older and a younger sister, also had a caring side, his family revealed.

“He was definitely a protector of his sisters,” Alex said.

Jagger’s siblings have since been tested for any underlying heart issues — but results have come back normal.

A fundraiser, which has raised more than $20,000, has been created to support funeral expenses.