BILLINGS — Matty Tomlinson is living his "summer of baseball" dream while fighting leukemia — and the sport is helping ease the pain of his relapse.
The 8-year old wears a backpack everywhere he goes, but not for fun.

"I can't take it off; it's going up into my port," Matty told MTN Sports.
The backpack is part of his 28-day, around-the-clock chemotherapy regimen, continuously infusing the medicine he needs.
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"So, when he has that backpack on his port is accessed. He can't get wet, he can't go swimming, he can't go fishing," his mother, Estaleda Webb, said.
Every week brings another medical hurdle.
"Every Wednesday I have to go back and get more Blina (Blinatumomab) … a bag change. Get a needle poke," Matty explained.
The family's home is about 60 miles away in Belfry. Through rigorous treatments this summer, Matty, his mom and grandmother have often lived at the Ronald McDonald House just a few blocks from Dehler Park. The family decided a "summer of baseball" was exactly what Matty needed.
"We try to give him little things to keep him excited," Webb said.

Kristi and Darrell Vavrosky wanted to add to that excitement through their Live Like Jace Foundation, which honors their son who was lost after a diagnosis of aggressive skin cancer. The Vavroskys decided to surprise Matty's family with Mustangs season tickets. When Kristi called the club, the Mustangs insisted on donating them.
"It happened kind of quick. We just realized that they were going to need season tickets and called the Mustangs. And within an hour and a half, they had season tickets," Kristi Vavrosky said.
The news brought Matty's mother and grandmother to tears.
"We were hoping for just a little bit of help because coming to every game every day does get a little spendy. When they reached out with season tickets we both just started balling. We were on our way to a game," Webb recalled.
The Vavroskys wanted to give Matty another special day, and on Friday rented a party tent in left field. But that wasn't all.
"And we knew that he wanted to go on the field and be by the players for the National Anthem and play hacky sack with the pitchers," Vavrosky said.

The Mustangs accommodated both wishes. Matty fit right in to the circle of pitchers — a moment he won't soon forget.
"Never been more excited," Matty admitted with a grin.
His journey is documented on his Facebook page, titled "Matty's fight against 'Zuchinia'" — a name with a story behind it.
"The first time he was diagnosed he was three years old," Webb remembered. "So, when we told him he has leukemia — that's a big word for a 3-year old — he heard "zucchini" ... zuchinia. For, I think it was four years I couldn't get that kid to touch zucchini because he swears up and down that's what gave him cancer."
As Billings prepares to host Missoula in Thursday's 6:35 p.m. Pioneer League playoff opener at Dehler Park, Matty is hoping this is the year of the Mustang — perhaps ending with a league championship. Either way, this summer of baseball is one he will never forget.