Michelle Key, 19 and her sister, Danielle, 16, will compete on racquetball's highest level when they represent Team USA at the World Racquetball Championships in Bolivia.

For these sisters, racquetball is certainly a family affair. With coaching from their parents, the girls' have quietly made a name for themselves.

“It’s always nice when your kids want to do something you want them to do without having to tell them or make them,” said the girls’ father Darold Key. “Because they will never have the passion to do it, if you force them to do something,”

"Me and my Dad have a really unique bond, “Michelle said. “We can be father-daughter and coach and athlete at the same time. Of course, there is a little bit of conflict here and there, but normally it’s really good."

"I think it’s always a pleasure, but it’s very difficult for parents to coach their own kids, to live with them and it’s really hard,” Darold said. “We never pushed them, so they asked us to help them get better at racquetball.

The girls' dad incorporates a well-rounded training regime for them and it's a formula they believe in.

"I leave all the coaching up to my Dad, so he tells me what to do, from the ladders that we do, the running, the jump rope, he's in charge of my hitting and all that stuff,” Michelle said. “So normally it’s up to him. My Dad normally does everything, so I'm kind of just there.”

The Key's have figured out the delicate balance between family and coaching, and now Team USA is benefiting.