I also have been following without getting involved since the advice given by 
others was so excellent I could not improve upon it.

When Faith mentioned a possible connection between sugar and mean behavior, I 
want to add my thoughts.

I had a similar experience with both my girls, the younger being the worst.  
She did not speak in sentences until age 11, had learning disabilities and 
attention deficit, conduct disorder.  She would run away, do drugs, steal money 
from my purse, shoplift.  When the girls came to live with my second husband 
and myself, I taught the younger one to read.(age 13).  I spent virtually all 
my 
time helping her to do her schoolwork which she couldn't have done alone.  I 
called her teachers to find out the homework.  If I didn't pick her up from 
school, she would disappear, to be returned by the police.  If I did pick her 
up, she would have her friends stationed along the path to her last class to 
call me dirty names.  She would call me "Jose" in front of her friends, my 
husband "Elmo".  Every evening, and sometimes into the weekday nights we did 
the 
homework together, against her protests.  She seemed to have no emotional 
attachment to the family," and would not be caught dead in the company of 
"grownups.  
She would try to upset me in covertly hostile ways, such as hiding items I 
would need to make breakfast.  Her hair was shaved on one half of her head, and 
she wore ghostly white makeup.  This continued throughout highschool with 
little change except that her grades went from Ds and Fs to Bs and As.  I can't 
underestimate the value of rewards versus punishment.  Of course, there should 
be consequences of bad behavior, but the more we can use rewards, the better 
the result.  When she got her first A, my husband and I shrieked at the top of 
our lungs in delight, and then called our friends to tell them, making sure our 
daughter could hear us.  From that point on she connected good grades with a 
positive self image, and continued to get good grades, even being able to sit 
for days on end alone to study for final exams.  At one point I grounded her 
for a year when I caught her letting her boyfriend into her bedroom during the 
nights. The lesson I learned there, is whatever we control controls us.  If I 
had not put in this effort (which continued through college, and to some 
extent in graduate school she would not have become what she is 
today--compassionate, responsible beautiful girl with graduate degrees.  She 
would be probably 
dead.  I gave ten years of my life to her (still requries a lot at 35), but I 
would do it again.  There was no way to completely prevent her controlling me 
as 
long as I was dependent, and ultimately I was and am still dependent, in that 
I do care that she has a good life.  I was able to overcome resentment about 
having my life controlled by consciously giving my entire life to her, and 
then any free time or small respite from hassle would be seen as an unexpected 
gift.  In other words, if I expected nothing else, I was not disappointed, and 
I 
consciously made the decision to continue helping her.  Therefore, it was my 
choice alone, for reasons that I well understood and valued (so ultimately, 
that made me in charge instead of my daughter). 

As I later discovered my own extensive allergies, I realized that much of my 
daughter's problems were due to allergies, and in fact, looking back I can see 
that she was borderline autistic.  She is now being treated for allergies 
with NAET.  I have seen her change physically and psychologically as she 
undergoes treatment.  The allergens affect the meridian that controls the 
brain, and 
that results in the psychological problems.  In addition to sugar there are 
many other possible allergens which could affect the brain.  One of the main 
allergies would be to B vitamins which are vital to nerve function.  

Jill