Hersey park or kings dominion?

I'm a 13 year old girl and me and my family are planning a vacation. We decided on either hershey park or kings dominion. The people going are.. Me. 13 yr old girl who's deathly afraid of any kind of big rollercoaster. My twin sister. Who likes rollercoasters but wouldn't go on the big scary ones. And My mom who is like me and my dad who like my sister. The other family coming with us is another girl my age, a 7 yr old boy and their mom and dad. I don't know if they like roller coasters or not. So can anyone tell me which park is better for people who want to have fun but don't like roller coasters? KingsDominion or HersheyPark? Both families LOVE water rides! So can someone please help?! Thanks so much!