*spoiler* why does Renesmee physically grow up so fast?

Question

someone told me that Renesmee will physically be 15 at the age of five. i don't get how her vampire side makes her do that.

Answer 1

There was really no *exact* explanation as to why she did, but it's because she's a hybrid of a vampire and human. Human grow slowly (usually) and vampires don't grow at all. It's just the combo of the two that make it so special. And yes she would be 15 at age 5, but she's not going to die. Remember Nahuel.  

Answer 2

well its kind of like jacob how he grew so fast because like how they were talking about how he has 24 choromosomes? and then like when edwards and bellas genes mixed edward has 25 chromosomes and bella well had 23 and then renesmee got 24. something like that.

idk thats my theory.lol

Answer 3

i'm not really sure how it works but when she turns 7 [human years] she will stop growing and look like a 20 year old, she will become imortal after this

Answer 4

it's magic.

Answer 5

Because it was convenient to Stephenie Meyer's tissue-thin plot.

Answer 6

Because she's a "mutant vampire" - a crossbreed of sorts. It all exists in Meyer's made-up world.