little girls, two sisters we haven't forgotten. One of them with a pair of scissors, the other with a new do afterward. And tonight, a new book. We'll never forget that tale, like so many parents, dad... See More
little girls, two sisters we haven't forgotten. One of them with a pair of scissors, the other with a new do afterward. And tonight, a new book. We'll never forget that tale, like so many parents, dad was just trying to figure out what happened between his two little girls. What led to this? Half of little Eva's hair gone. So, he sat 5-year-old Sadie, 3-year-old Eva down, recorded the whole thing, asking how the little sister agreed to this. Eva, do you want to take your hair out of your braid? And then I got the idea of trimming her hair. Reporter: That's right. The 5-year-old thinking the 3-year-old could use a trim. And the 3-year-old corroborated the story. Do you want me to cut your hair and I said yes. Reporter: Sadie went to work. I climbed up on the bathroom to get the scissors and I just kept cutting and it was like, so hard to cut, I was like, la, la. But then the hair kept slipping off the scissors. Reporter: And the result, Eva with a bob on one side and not the other. I look at her and I think, uh-oh. This is bad, bad, bad. Reporter: And then mom saw little Eva and both girls remember that. Sadie, Eva, what were you thinking? Louder than that. Reporter: And then dad, who actual sli a reporter for NPR, digging for more answers. Asking at the time -- What did you do with the hair? I hid it under the radiator. Reporter: Hid it under the ray yeah or the. But the parents, like so many moms and dads, saw an opportuni opportunity, to teach their girls about mistakes. Everyone makes them. And everyone should learn from them, too. It happens, like, once. Or twice. Reporter: Tonight, mom and dad have sent us a new picture. Look at Eva with the pigtails. Her hair is back. Now dad has written a book about the worst haircut ever. And here's what little Eva told me late today. What do you hope the lesson is for everyone who reads your book? Not to cut people's hair. Reporter: She told me she knows everyone makes mistakes, but for her, not that one. Never again. Thank you, Eva. Thank you, David. The hid the hair, but it's all back.
This transcript has been automatically generated and may not be 100% accurate.