Once I told a Mom that my eight-year old lovely daughter 
always wanted to give me a hug. The Mom said his son used to
do exactly the same to her, but things had been changed ever
since he became ten: no more. 
 
I told my daughter this story right after this conversation.
 
Now my daughter is between thirteen and fourteen but she still comes to 
my bed side every night for a hug. Occasionally she would mention the 
story I told her many years ago just to check if what happened to that 
Mom would ever happen to me. 

*** Added June 23, 2007 ***

最近有了两个Teenage女儿（一个刚进入十三，一个即将二十）的一个父亲跟我讲,
They only have two states: laughing and crying, nothing between. 他告诉女儿说， 
They are no longer friends to him, until they are out of teens, when they 
(daughters and himself) will become friends again and talk again.