They borrowed a bat and met the coaches that day. Two days later, when they showed up for practice, his mom, Beth, was working the concession stand. From that day forward, the Butlers were a ballpark family.
"Billy always looked like he knew what he was doing, even at that early age when he hadn't really learned anything about the game," JD said. "As dads do, I got recruited to coach, so I signed up to coach and we played every year, spring, fall, summer and never took a year off."
In addition to playing every spring, Butler also suited up for Team USA every summer from when he was 15 years old, and his dad was always there, usually as the first-base coach.
"If he wasn't so vital in my younger days, I would have never kept up with baseball," Butler said. "At some point, your dad has to motivate you until you actually realize what you're doing. When I turned 12 or 13 years old, even as a dad, you can't make a kid play anymore, but up until that point he pushed me to keep playing and when I turned 13, I didn't want to do anything else. He was just there with me at the cage every day because I wanted him to go with me and throw to me and work on what I needed to work on."
All that work paid off when Butler was offered a full-ride scholarship to the University of Florida and then drafted by the Royals in the first round of the 2004 First-Year Player Draft. He was the 14th overall pick.
"I remember when he was a little dude and said, 'Dad, I'll make it to the big leagues some day,'" JD said. "As a father, when your 6- or 7-year-old kid tells you that, you support those dreams and that's what they are. Anyone who says 'My 8- or 10-year-old is going to be a big leaguer,' it is probably a pretty farfetched goal, but that is a dream everybody has. He's an All-Star, that's a dream, and he made it to the big leagues and he is established. I think anything after that are his dreams now. All of my dreams have come true."
Butler's been with the Royals organization for nine years now with an All-Star Game appearance and American League Silver Slugger Award last season. He also led the Royals in all three Triple Crown categories.
He gives his father credit for teaching him how to work hard. JD worked as a structural engineer for Boeing, for whom he is now the senior quality manager for strategic missile systems.
"If we are going to do it, we are going to do it to the best of our ability," Butler said. "I think that's why I'm such a good hitter, because he told me if I'm going to do something, I'm going to do it right. It's going to be physical inabilities, it's not going to be because you didn't work or you weren't prepared. That's how I go about it every day."
Though they've passed the days of baseball instruction, the two still talk every day through texts or phone calls. Butler even asks him for advice sometimes.
"An All-Star, a .300 batting average in the big leagues and he still looks for my approval in everything that he does," JD said. "He's got George Brett as a hitting coach now and he still comes back and says, 'Dad, what do you think? What did you see?'"
JD and Beth recently moved to Scottsdale, Ariz., where Butler lives in the offseason with his wife, Katie, and two daughters, Kenley and Karsyn.
"He's past the baseball, he doesn't really care about the baseball anymore," Butler said. "He's got two grandkids. He comes out and he just wants to spend time with them. He can't wait till the game gets over so we can hang out. Baseball is what it is to him and he put the time in. He's at a different chapter in his life now."
Butler's starting a different chapter, too. His oldest daughter Kenley, who is four years old, is just starting T-ball and just like his father did for him, Billy tries to go out with Kenley and hit off the tee every chance they get.
"I never go to bed at night worried that my grandkids aren't taken care of, because they both realize the responsibility of being parents," JD said. "Billy's challenge is, he's got two girls and they're both very young. Big ol' guys don't know what to do with girls when they're that age. Probably the best word would be overmatched. He's definitely beat before he ever gets started, but he does the things he needs to do. He's being the kind of role model I would expect him to be."