As the Islanders’ new co-owner, Jon Ledecky is boss to a number of world-class athletes, including one of the best hockey players on Earth in John Tavares.

But he has a personal relationship to an even more rarefied athlete in Katie Ledecky, a 2012 Olympic gold medalist who at 19 has grown into a multiple world champion, multiple world record holder and favorite to be a multiple gold medalist in Rio next month.

She is Ledecky’s niece, the daughter of his brother, David. He plans to be in Brazil to witness all her races.

“I’m going to go to Rio, because fortunately that dovetails with the deadest period in the National Hockey League,” he said Wednesday at a get-acquainted luncheon with journalists in Manhattan.

“I know when [GM] Garth [Snow] is on vacation with [coach Jack] Capuano off as well, that’s got to be the deadest time, so that worked out well. That Aug. 4 to 15 period is when most guys take their vacation in the NHL.

“NBC has been very kind. They put the family on TV a couple of times and mentioned Uncle Jon and mentioned the Islanders, which is nice. It probably will be a little harder for them to do that in Rio. It’s a big place. But for the Olympic trials in Omaha it was fun to see her swim.”

advertisement | advertise on newsday

Ledecky called Katie “a delightful young lady, and she is an amateur and she’s going to Stanford in the fall and she’s a hockey fan. She grew up when I was associated with the Caps. I used to be a minority owner of the Caps with Ted Leonsis. She was introduced to hockey.

“And there’s an iconic photo of her [in a luxury box as a toddler] coloring in her coloring book when we brought Michael Jordan back as an owner and he eventually became a player for the Wizards, which we also owned.

“So she was around great athletes from the beginning of her life, and it seems to have rubbed off. She’s quite the swimmer.”