Yes they roar at times, they move at times but its rather subtle and about every 15 minutes there is a "meteor shower" where its louder with thunder and lightning but it doesn't last long. I can't tell you about a little girls reaction from personal experience but I can say that I took my nephew at age 3 (almost 4) last year and age 5 just a few weeks ago and he loves it! There is so much to do and see but its not overwhelming. I saw kids of all ages there and I can't say that I saw any of them that seemed to be scared or upset. In fact most of them were not eating during all the action just to be able to watch all that was happening. I think there are some of the seating areas that are a little more secluded than others but nothing keeps you away from the meteor showers. On a side note though - unless the girls are dinosaur fans you might look into Rain Forest Cafe, same food basically, same "showers" but the animals aren't as scary , we ate there on our recent trip too and he enjoyed it just as much esp the larger gift shop ie more choices for his surprise gift from my 14 yr old nephew.