My daughter (11 yo) has been really back and on forth on roller coasters through most of her life. Lagoon is our home park and over the last 8 years we've visited Hersheypark a few times, Disneyland/Disneyworld, and Legoland (CA and FL). She would try something new and I thought she was going to try bigger rides, then suddenly she'd get afraid again. But last summer, something suddenly switched. She was riding Colossus at Lagoon and loving it, just like her old man, then at HP last summer she decided to try Candymonium and rode it 9 times in a row. This year we were back at HP, she started at Skyrush and rode everything else with no issues. She was probably most nervous for Stormrunner but it ended up being her favorite.
Just sharing my experience because I wasn't sure which way it was going to go until last year when something switched, and it all seemed random. She's the youngest and I have two older boys. The older is very afraid of heights, the younger gets sick on rides. And now my daughter can't get enough of roller coasters, and I'm looking forward to taking her to a lot more parks.