It's been a rough time for 8-year-old Perryn Miller from Wilmington, North Carolina.

"It's been a whirlwind. It's been hard. But it's been overwhelming awesome at the same time," said his dad, Jacob Miller.

While visiting relatives in Utah for the holidays, Perryn started getting headaches, and a trip to the emergency room revealed a brain tumor.

Perryn Miller CBS News

"We've been happy that Perryn made it out of the surgery. We've been shocked, we've been sad," said Jamie Miller, Perryn's mother.

Now he's had some smiles, too. The West Valley, Utah, police department named him officer for the day. He got to meet his favorite soccer player, Justen Glad.

But nothing was quite right until Frank showed up. Frank is the Miller family's 8-month-old German shepherd.

"I felt really excited to see Frank. I just really like Frank and he's a good dog," Perryn said.

Frank had been left behind in North Carolina until the family's story hit social media. That's when a former trucker named Bob Reynolds, who didn't even know the Millers, decided to pick up Frank and drive 2,300 miles in 52 hours to deliver him.

"I never questioned why I was doing it or anything like that. I just knew something had to be done and that I could do it," he said.

"One time when we were just laying down snuggling, a tear went down. He cried and I felt loved," Perryn said.

So how will Frank get home? Reynolds has already volunteered to make the trip all over again.