(OPRAH.com) -- Growing up with three brothers in Houston, Diana Lopez experienced the same good-natured torture most sisters undergo at the loving hands of their older siblings.
Of course, most girls didn't have to defend themselves against champion martial artists.
Not one to back down from any challenge, the 25-year-old soon followed suit, becoming a tae kwon do champion like her brothers.
Lopez and two of her brothers -- Mark and Steven -- made history in the 2008 Olympic Games in Beijing as the first family to have three siblings on the same U.S. Olympic tae kwon do team.
To boot, eldest brother, Jean, led them as their coach. In their new book, "Family Power," the Lopezes detail their efforts and their parents' support in helping them succeed.
Diana shares how years of hard work, determination and unwavering support in each other led them to earn medals in the sport, with Jean coaching them to victory.
Erin J. Shea: Your family's story is very much the quintessential American dream story, but immigrating to a new country and starting a family is not without its challenges to overcome. What were those challenges your family faced, and how do you think they served as a foundation for your collective futures?
Diana Lopez: My parents came from a Third World country [Nicaragua], and they only spoke Spanish. Instead of going to Miami or someplace where a lot of Latinos were living, they went to New York City. I don't know how my mother did it. My dad was in his 30s, and she was in her 20s. They had to start over.
My mom's philosophy was that [America] was where they were going, and once they got here, they were going to do what it took to make ends meet. To this day, my parents don't tolerate complaints. You work hard, no matter what. If you're going to be a custodian or work in a fast food joint, you're going to be the best in whatever you choose.
ES: Tell us about your early days of tae kwon do. I understand your father enrolled Jean to help build his self-confidence. Was it an immediate love affair with the sport for everyone, or did that passion grow over time?
DL: For me, [tae kwon do] was something that I thought I was supposed do. No one actually asked me if I wanted to do it. I didn't know anything different. What I enjoyed most at first was getting to travel to different states with my family.
That was our vacation. We'd have to make up games on our road trips. It was fun hanging out with my family, and I'll cherish those moments forever. My dad was always into martial arts. And when were growing up in New York, there was a school across from where we lived. Jean fell in love with it and paved the road for us.
We all fell in love with it then. It's weird, because I see different families, with siblings who all play in the same sport, so I think it's something in your genes!
ES: Siblings always play varied roles within a family. What are the roles that each of you played? Has that dynamic helped you achieve such feats?
DL: My brother, Jean, is the top of the pyramid. He paved the way and made it easy for us. He was the one who moved to the Olympic Training center early to teach us things we didn't know in our sport. He really is like a second father, coach and a guidance counselor.
Steven is our hero. He's won two Olympics and five World Championships. If I ever have a question about tae kwon do, I ask him.
Mark is our superstar, the showman. He plays with the crowd. I'm just the baby only girl, and my brothers say I'm the princess, but I don't think so.
ES: In your book, you talk about the "doubters" and people who didn't believe in you. What was the point where you realized you had to be each other's biggest cheerleaders because of the negativity you faced?
DL: You'll always have negativity everywhere. That was something my parents taught us. But if you don't trust your own family, who will you trust? For me, any negativity motivated me, especially those who would question if I was as good as my brothers.
Sometimes it was even my brothers who asked it. But if they slept in, I'd go run. I've always worked extra hard. Overall, we always had support for each other and kept each other going. If I was tired, Steven would grab me to go work out. We never knew if we'd have that chance [of competing at the Olympics] again.
ES: So much is made of sibling rivalry, and yet you've all seemed to overcome it. How were you able to foster a positive environment between each other, one that encouraged each person to strive to be better, while at the same time supporting each other?
DL: People are always ask if we fight, and we do. Believe me. But I think if Mark and I didn't make the Olympic team, we knew there would have been nothing we could have done.
We would have been right there cheering on our brother. If he wins, it's a win for all of us. We're unique in that each of us knows what the other has been through and sacrifices we've made to get here.
We are very competitive, though. Whenever there's a game of Taboo or poker, watch out. There is no such thing as "friendly poker" with us. Blood pressures are going up, believe me. I think since martial arts is all about self-discipline and respect -- we're cordial even when we fight each other -- we do act like normal siblings in other areas.
ES: Throughout the book, each of you writes with such a sense of compassion about the other and this very innate sense of who each is, while at the same time no one is out on a pedestal. Did the sport help you all with that or was it something else?
DL: It was a combination of sport and family. My dad gave Jean authority with us, but Jean never abused it as our older brother. Even when it was rough for me with them, I knew they always wanted the best, and they never crossed the line. My dad had a great deal of sense about how he wanted to raise his family. No one is ever allowed to disrespect each other.
ES: What would you say is the secret of your relationship with each other?
DL: We're not big talkers, but if one of us senses something is wrong with another, or even if they're happy, we know each other well enough to know what to do. We can just look at each other and know what's going on. We don't have to speak. I think that's what has always successful in the ring. I can look at Jean when I'm in ring and I have a sense of relaxation, with just a nod.
ES: As you've all gotten older, how have your relationships changed?
DL: I knew growing up that we weren't going to be in the same house forever, that eventually they'd have to leave. [But] it was weird for me to see them have their own families. I was always the baby, and now my brothers have their own little guys running around. So now we get to see all these the different families forming from ours. It's beautiful.
ES: What advice would you give to someone looking to grow in her relationship with her siblings?
DL: It's all about communication. If you have a problem, you have to have those [TV] moments when you all get together in the end to have a talk. Speaking is part of every relationships, and you have to communicate your feelings. Never leave things out.
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