Kelsey McCaffety was at her softball game last month when she learned the devastating news that her parents, Clint and Meghan, as well as her older brother Connor had been killed in a car crashHer family members were driving back for one of Connor's games, and when Kelsey heard that the athletic director wanted to cancel it, she wouldn't hear of it — and she wanted to be the one to tell the team"Her grandmother, her Mimi, told me that she's just been the rock for the whole family," coach Brandon Puffer, 49, tells PEOPLE Kelsey McCaffety was pitching in a softball game on March 31, when she was told the tragic news that her parents and older brother died in a car crash. The day they died, Clint and Meghan McCaffety, along with their son, were driving from College Station, Texas, where Connor, 17, had competed in a golf tournament. They were on their way back to their hometown of Rogers, where Connor and his sister both had games to play in. After learning what happened, the school district athletic director told Kelsey, 14, he was going to cancel the game Connor was slated to pitch in and tell his teammates — but Kelsey wouldn't hear of it, according to Brandon Puffer, Connor's private pitching coach. “Kelsey said, 'No, no, no, Connor would want them to finish the game,' " Puffer, who was not there but spoke with the athletic director, tells PEOPLE. "And she said, 'I want to be the one to tell them. Those are his brothers.' " “The strength of her receiving this news – and then thinking about others and how to break it to them,” adds Puffer, 49, a former MLB player and founder of GPS Legends Baseball. “Her grandmother, her Mimi, told me that she's just been the rock for the whole family. We're all praying for her and doing whatever we can to support her." According to her brother's obituary, Kelsey has many surviving relatives, including multiple sets of grandparents as well as aunts, uncles and cousins. Puffer met the family about four years ago when Connor was an eighth grader starting travel baseball. “Every time you saw them, they were kind,” he says. “They were always together." “They’re such an amazing family,” Puffer adds. “It was very normal for Connor and his dad or his mom, to drive an hour and a half for a private pitching lesson, so maybe they're spending three hours in the car together just to give Connor that opportunity to get a little better." Clint, who owned a construction business, also worked around his children's sports schedules. “That's just what the family did," he adds. "They supported each other in everything Kelsey and Connor wanted to do. Clint and Megan just made it possible. That was their whole life." Never miss a story — sign up for PEOPLE's free daily newsletter to stay up-to-date on the best of what PEOPLE has to offer, from celebrity news to compelling human interest stories. In addition to sports, the siblings were both active in Future Farmers of America, raising steer — and in the aftermath of the tragedy, a steer was auctioned off at the Milam County Livestock Auction last week, raising $180,000 to support Kelsey. “I knew we had amazing people in my family that passed, but I didn’t know the impact that they had on these people. The impact they had on those people, are now making the impact back onto me,” Kelsey told CBS affiliate KWTV. Known as "Bubba," "Big Puma," "Big Mac" and the "Gentle Giant," the 17-year-old high school junior, who was six foot five, was also a member of the National Honor Society — but "baseball was definitely his passion," says Puffer. With an eye to the future, the coach says he was already starting to talk to college scouts about the “big teddy bear” who was an amazing pitcher with awesome change-ups. Puffer is confident Connor would have played college baseball, like his father, and possibly gone pro. “He had great potential,” the coach says, and he was fun to watch. His coach adds, “You had to love him."