This story was originally published by Steve Helling on PEOPLE.com.

Tim Tebow is opening up about his family’s latest challenge.

“My dad has Parkinson’s disease,” the former quarterback turned baseball player tells PEOPLE in its latest issue. “He was diagnosed last spring.”

Both Tebow and his father, Bob, sit down with PEOPLE in their Jacksonville homes to talk about the diagnosis – and how it changed their lives.

Tebow, 29, recalls getting the bad news while he was in an Atlanta hotel room. “Talking to him that night, I wished that I could have been there with him. I asked him whether he needed me to come home, and he said, ‘No, you need to keep doing what you’re doing.'”

Despite his father’s reassurances, the diagnosis was difficult for Tebow to hear. “It wasn’t a good night,” he recalls. “I got really emotional. I mean, this is my dad.”

The news was a reality check for Tebow, who was inspired to reassess his priorities. He began spending more time with his father. “I love being around him,” he says. “We watch ball, talk ball. But I also go to him for advice about spiritual questions. There are times where he sees something from a different place than I do.”

Case in point: Tebow says that he has become “drastically protective” of his father, carrying his luggage and helping him with difficult tasks. But Bob Tebow tells PEOPLE that the diagnosis doesn’t change his outlook at all. “I’m not going to retire from the Great Commission to spread the gospel,” he says, referring to his mission work. “I may be slower, and I may shake on the way, but I still have work to do.”

Shortly after his diagnosis, Bob Tebow headed back to the Philippines to visit orphanages, prisons, and the Tebow Care Hospital, a five-story facility that opened in 2014.

For Tebow, it was nice to see his dad in his element. “When you see Dad in a third-world country with hurting people, you’re like, ‘that’s what he’s meant to do,'” he says. “It’s his most comfortable place to be in the world.”

Now playing for the Fall Instructional League for the New York Mets, Tebow says that his dad is never far from his mind.  “I’m playing for him, and I’m playing for myself,” he says. “He loves to come watch me, and then to talk about it later. It’s one of the ways we spend time together.”

And despite the devastating diagnosis, both Tebows tell PEOPLE that they are at peace with whatever happens next. “You never know how much time you have on earth,” says Tebow, “but my father has an incredible legacy that has nothing to do with me. I’m so proud of him.”

For much more about how the diagnosis has changed Tebow’s life, love and career, pick up the latest copy of PEOPLE, on sale Friday.

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