Harry is fourteen yes and acts more childish. I'd like to point out though that I do know a fifteen year old boy, my own adopted cousin, who suffers from past child abuse and abandonment by everyone he knew. He acts like the Harry in this story - this fanfic is a sort of tribute to him. There is nothing wrong with the way he acts, it's just the way some people cope.
I'd also like to point out that I am a nineteen year-old 5'7" female and can easily carry said fifteen year old cousin around. It is realistic, just not common. And also calling your father/father-figure Papa does not have a time limit. I, my twenty-two year old older brother, and my two younger sisters (both in high school) all still and probably always will call our father Papa. Deal with it.
*Sorry, I just had to rant at some reviews and PMs I've been getting lately. Normally I ignore or laugh at flames/bad reviews but I love my cousin and am extremely protective of him. This story is for him and it ticks me off the way ignorant people are acting like they know everything about all kids and abused peoples.