Six years ago, world-famous daredevil Nik Wallenda dangled from a trapeze attached to a helicopter hovering 250 feet above a Missouri theme park.

He wowed onlookers with the precarious stunt by hanging from the trapeze with the grip of his toes. Then he resurrected one of his grandmother’s old tricks, the “iron-jaw hang,” by dangling this time from just his teeth.

The stunt set an iron-jaw hang Guinness World Record for height.

At 8:30 a.m. Thursday, his aerialist wife with her own rich circus lineage stole his title — from 300 feet above the raging waters of Niagara Falls.

Erendira Wallenda was just high enough to avoid the mist and pesky wind currents that come with the fall as she performed an elegant acrobatic routine, weaving in and out of a hula hoop during a routine choreographed to music. She dangled from her knees, her hands, her toes and, just like Nik did in 2011, only her teeth.

“If a guy can do it, a girl can do it, too,” she said after the stunt.

Her husband, Nik Wallenda, has called her a “ballerina in the air.”

The aerialist wore a cable tether around her waist, in accordance with a New York state law that requires a safety support for aerial stunts above 20 feet, but it didn’t aid her performance. It was only there to catch her if she fell — which she never did.

Nik Wallenda watches from above as his wife, Erendira Wallenda, hangs by her teeth while suspended from a helicopter above Niagara Falls in Niagara Falls, N.Y., on June 15. (AP/Bill Wippert)

It all happened on the five-year anniversary of one of Nik Wallenda’s most impressive stunts: his televised tightrope walk across Niagara Falls.

“I remember watching Nikolas as he was crossing the falls and thinking, ‘Boy, I wonder what that would feel like, I wonder what that would look like,’ never thinking that five years later I was going to get the same opportunity,” Erendira Wallenda said at a news conference the day before. “I just feel blessed.”

Husband and wife come from world-famous circus and daredevil families.

Nik Wallenda helped revive his family’s 200-year-old legacy by performing death-defying stunts on live television, such as walking on a tightrope across Niagara Falls and the Grand Canyon.

The signature stunt of the Flying Wallendas, as their troupe came to be known in the 1940s, was the seven-person chair pyramid — an act that went fatally wrong in 1962. The stunt involves four acrobats on the tightrope holding two more acrobats above them. A third performer, usually sitting on a chair and at his teammates’ mercy, teeters at the top. During a performance at the Detroit State Fair, the Wallenda pyramid toppled, sending two troupe members to their deaths and leaving a third paralyzed.

Other Wallendas, including Nik Wallenda’s great-grandfather, have fallen to their deaths while performing.

Erendira, a lifetime aerialist, is the product of eight generations of circus performers on her mother’s side and seven generations on her father’s side. Her mother’s family runs the third largest circus in Australia and her father’s family is part of a circus in Mexico City that now travels the United States.

“It’s hard to marry somebody who doesn’t walk a wire,” Nik Wallenda said Wednesday, “who doesn’t risk their life.”

He said the goal was to get through the stunt without slipping, and emphasized that dangling from your teeth is “extremely painful.”

“It hurts really bad,” he said.

Nik Wallenda walks eight stories above the Chicago River during Discovery Channel’s Skyscraper Live with Nik Wallenda in 2014. (Jean-Marc Giboux/AP Images for Discovery Communications)

He first performed the iron-jaw hang five years ago to pay homage to his grandmother and grandfather, both Wallenda family performers who used the stunt in a routine together. His grandfather would ride a bicycle on a tightrope while his grandmother dangled from her teeth below it.

Back then, the only mechanism keeping her in the air was her tight bite on a folded leather belt.

Now, with the help of modern technology, Nik and Erendira rely on the help of their dentist, a close family friend who built mouth guards molded to their bites.

The couple has strong toothpaste — and a “very understanding dentist,” Nik Wallenda said.

“Obviously, my dentist doesn’t want me to do this for the rest of my life,” Erendira added.

The helicopter took off at 8:30 a.m. from the roof of the Seneca Niagara Casino parking garage and returned by 8:50 a.m. Throughout the entire stunt, Nik Wallenda rode on the helicopter, watching her routine for hand and body signals they’ve come to recognize in each other during their 17 years of marriage.

The two share three children, all of whom are adept in the air but have shown limited interest in carrying on the family business.

It was as children watching their parents perform that Nik and Erendira met. He was 3 years old and she was 3 months. Their friendship evolved into romance as teenagers. When Erendira turned 18, they married.

“I really did marry my best friend,” she said at the news conference. “And not too many people can say they married someone with the same passions that they have.”

They spoke of their fascination with Niagara Falls and their long-held hope that one day, the family will find a way to build a permanent performance center on site.

“It’s an incredible force of Mother Nature,” Nik Wallenda said. “I don’t think people realize the magnitude of Niagara Falls around the world.”

Niagara County and the city of Niagara Falls each set aside $35,000 to help fund the stunt, and the Seneca Gaming Corp., the event’s lead sponsor, gave $50,000, reported the Buffalo News.

The idea for Erendira’s stunt came as the couple was brainstorming how to commemorate Wallenda’s Niagara Falls tightrope walk in 2012.

“Remember that world record that you set years ago hanging by your teeth under a helicopter about 200 feet above the ground?” Nik Wallenda recalled his wife saying at the time. “Well, why don’t you allow me to do it 300 feet above the falls?”

“I was like, ‘Absolutely,'” Wallenda said he responded. “That’s amazing. That’s awesome.”

But according to a quip he made during the news conference, the unabashed one-upper doesn’t plan to let his wife keep the record for long.

“In five more years,” he joked, “I’m going to hang by one tooth, 800 feet above the falls.”

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