The first time I took my eldest son and his daughter to WDW she really wanted to ride Rock'n Roller Coaster, but he wouldn't let her. He said she'd be too scared. Now my eldest son is a ride whimp, whereas my GD is a little daredevil and afraid of nothing. She put both hands on her hips and rather loudly said, "Who's scared dad, me or you? You're the chicken". Anyway I offered to go on with her, but for some reason he wouldn't let her.
A year later I took her back down there by myself for a GM-GD alone time trip. She hadn't forgotten about Rock'n Roller coaster and one day a week or so before the trip, glared at her dad and blurted out that she was going to ride it this time, "because Nana's not a chicken like you".

I looked at my son, who shrugged, and told me to do what I wanted, but not to blame him if she got scared. Anyway, when we got to DS, she made a beeline to it. I asked her repeatedly all through the line if she was sure. She got really agitated with me and told me she knew what she was doing and couldn't wait. Anyway, once we got on the ride she reached up to pull the restraints down, then started looking for a seat belt. When I told her the overhead restraints was all she needed and all the ride had, she panicked. She started yelling, "what do you mean they don't have seat belts?" We took off immediately after that, and she screamed bloody murder throughout the ride that she was going to fall out. After we got off, she got really quiet and I asked her if she was OK. She said yes, so I asked her if she liked it and she said, "sort of". I then asked her if she wanted to ride it again and she said, "Let me think about it". She was so quiet, that it kind of scared me. By this time, we were walking out of the building and into the area where all the people who don't ride sit around and wait. Anyway, suddenly without warning she puts both hands on her hips, stomped her foot, and screamed really loud, "What were you thinking, letting me go on that ride. I could have been killed. I thought you loved me". I started laughing and reminded her that she had been insisting for a year that she was determined to ride that ride. She again stomped her foot, kept both hands on her waist and yelled, "What do I know, I'm a kid. Geez, you're supposed to be the adult". She had the most disgusted look on her face, it was hilarious. I'm sure all those people standing around waiting for their families to get off the ride thought I was the worst GM around, but they were all rolling with laughter.

My GD was about 8 y/o.