"Duck Dynasty" star Jep Robertson makes a startling confession in his upcoming book, "The Good, the Bad, and the Grace of God: What Honesty and Pain Taught Us About Faith, Family, and Forgiveness," that he co-wrote with his wife, Jessica.

The youngest Robertson son claims that as a 6-year-old child, he was abused by an older girl on the bus to school. He kept the information hidden from his family, but finally opened up to his wife.

"Back then the high school students would ride on the same bus as the grade school. There was this girl there that was just real mean... I don't know but it was a lot of things took place - scary stuff. It was tough," the 37-year-old reality star told Entertainment Tonight.

He explained that the girl would make him touch her in inappropriate ways. "I didn't know what was going on, but I knew something wasn't right," Robertson said.

Afraid to board the bus with her, he racked up "a lot of absences" and had his mother, Miss Kay, believing he was just sick. Although he tried to forget about the abuse, Robertson says he was "scared of girls and women" long after.

He also struggled to tell his parents what had happened to him in fear of hurting them.

"I don't know if I necessarily consciously wanted to [keep it a secret]," Robertson said. "I was more embarrassed. I think in the end I didn't want my mom and dad to think they did anything wrong, and they didn't."

Robertson and his wife have four children together - three daughters and one son. He credits his girls for helping him overcome his discomfort around women.

"I know it sounds weird but it's helped me now that I have a bunch of girls. I think it helps us really communicate with them on what's right and what's wrong," he said.

"The Good, the Bad, and the Grace of God" will hit bookshelves on June 23. "Duck Dynasty" returns to A&E on Wednesday, June 24 at 9:30 p.m.