my son is three years old this month

He can only account 1,3 , 4, 5 always miss 2.can write only 1, he recongize only 1 if I write 1-5, but he smells all the time, I am happy as long as he is happy with what he is playing, I have no doult he is a clever boy.my friend's girl ont two years old yet, she can count 1-10 and recongnize corlors, likes reading,but i never compare them because they are just different......