Some parents thought they were misinterpreting the doctor's techniques. Others assumed their children were lying or mistaken.
But as more details emerged, the mothers and fathers had to face an awful truth: A renowned sports doctor had molested their daughters.
These parents, many fighting back tears, confronted Larry Nassar during his long sentencing hearing, lamenting their deep feelings of guilt and wondering how they could have missed the abuse that sometimes happened when they were in the same room.
"I willingly took my most precious gift in this world to you, and you hurt her, physically, mentally and emotionally. And she was only 8," Anne Swinehart told Nassar. "I will never get rid of the guilt that I have about this experience."
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Many of the young athletes had come to Nassar seeking treatment for gymnastics injuries. He was sentenced Wednesday to up to 175 years in prison after admitting sexually assaulting athletes under the guise of medical treatment while employed by Michigan State University and USA Gymnastics, the sport's governing body, which also trains Olympians.
He counted on his charm and reputation to deflect any questions. He was so brazen that he sometimes molested patients in front of their parents, shielding the young girls with his body or a sheet. His clinic on the university campus was decorated with signed photos of Olympic stars, bolstering his credentials to star-struck athletes and their families.
Parents who voiced concern say Nassar dismissed their questions. The mother of one 12-year-old victim said she questioned Nassar about not wearing gloves and he "answered in a way that made me feel stupid for asking."
"I told myself, 'He's an Olympic doctor, be quiet,'" the woman said. "The guilt that I feel, and that my husband feels, that we could not protect our child, is crippling."
Some victims said they were so young that they did not understand they had been abused until they were adults, so did not tell anyone.
What's more, coaches told the parents that Nassar was the best and could help their daughters achieve their dreams.
Paul DerOhannesian, a former prosecutor in New York who has written a book on sexual assault trials, said abusers in positions of authority often hold "tremendous power" over both children and parents. Some parents also fear what will happen to their child if they report abuse, including whether there will be repercussions for the child.
"It shouldn't turn into a situation where we blame parents," DerOhannesian said.
But even when Nassar's abuse was reported to coaches and law enforcement authorities, many of them did not believe Nassar had done anything wrong, causing many parents and girls to second-guess themselves.
Donna Markham recounted how her then-12-year-old daughter Chelsey began sobbing in the car as they were headed home after a session with Nassar.
Her daughter said, "Mom, he put his fingers in me and they weren't gloved," then begged her mother not to confront Nassar, fearing it would derail her gymnastics career.
The next day, Donna Markham told her daughter's coach, who did not believe it. Markham said she also asked other mothers if their daughters had mentioned inappropriate touching by Nassar. "They gave me a look like, 'You're lying to me,'" she told the judge, choking back tears.
Chelsey Markham quit gymnastics not long afterward and entered a "path of destruction" and self-loathing and eventually committed suicide.
"It all started with him," Markham told the judge. "It has destroyed our family. We used to be so close. ... I went through four years of intense therapy trying to deal with all this, until I could finally accept the fact that this was not my fault."
Some parents did not believe their daughters at first, finding it incomprehensible that the man they trusted could have done anything wrong.
Kyle Stephens, whose family was close with Nassar's, said he repeatedly abused her from age 6 to 12 during family visits to his home near Lansing, Michigan. But her parents did not believe her when she finally told them and made her apologize to Nassar.
Years later, her father realized she was telling the truth, and she blamed his 2016 suicide partly on the guilt he felt.
"Perhaps you have figured it out by now, but little girls don't stay little forever," Stephens told Nassar. "They grow into strong women that return to destroy your world."
Dancer Olivia Venuto, who said Nassar abused her from 2006, when she was 12, until 2013, said her parents did not believe her at first and sent Nassar messages of support after a 2016 Indianapolis Star investigation revealed the abuse.
Swinehart said that when her 15-year-old daughter, Jillian, told her she had been abused, "I tried to believe that there was some medical necessity for this treatment," she said. "The alternative was just too horrific, to think that I had let this happen to my child when I was sitting right there."
Police in Michigan investigated Nassar twice. One inquiry from 2004 concluded that his actions were medically appropriate. Another investigation in 2014 and 2015 did not result in charges.
Judge Rosemarie Aquilina, who sentenced Nassar, told parents not to feel guilty. "The red flags may have been there, but they were designed to be hidden," she said.
Swinehart said other people can't know how they would have reacted in the same situation.
"Quit shaming and blaming the parents," she said. "Trust me, you would not have known. And you would not have done anything differently."