PLEASE HELP! How do I convince my parents to permanently straighten my hair?

[Marnie]

Im 13 and I have natrually curly hair, not perfect curly like people on tv, my hair is REALLY poofy and frizzy at the front! I straighten my hair almost everyday, and im worried about damaging it! Heaps of people I hang out with always say things to me like "omg i love your hair" or "ahh, your hair is just so amazing and straight!", but thats cauz i always straighten it and they dont know what my natural hair is! I dont want to go swimming when im invited to the beach, because im embarresed about my curly hair and i dont want it to dry and go curly. I REALLYYY want to get it permanently straightened, I know what treatment to get and everything! I've done sooo much research but my parents just dont understand! They always say the same thing "your too young, its too damaging for your hair" and tell me I can get it when im 15 (2 years), but thats too long! How am i meant to avoid going to the beach for 2 years!? And whats the difference about my hair when im 13, and when im 15, its still the same hair! Anyway, does anyone know what I should say to them to help me convince them? I reallyyy want it to be done and I would really appreciate if someone helps meee! Dont bother commenting anything like "ermegherddd dont get it done your lucky you have curly hair" because you dont understand what its like! Im getting really stressed out its the only thing i want right now but i dont know what else to say to convince them :'( PLEASE HELP MEEEE! <3 <3 :'(