>Following is my opinion.  If your son is thin, good for him.  As someone
>who grew up fat and was scarred by the experience, I respectfully question
>your motivation for wanting to "fatten him up".
        In defense of wanting to fatten up the skinny kids.  Heavier kids grow
taller.  (Prob. too much insulin.)  But I have noticed that the boys who
put on a little bit of weight, then have a growth spurt.  I am not saying
that they should be fat, but all my kids are the shortest and lightest in
their classes.  FWIW, I was the smallest kid too til 10th grade.  And a
child who is thin at adolescence will never be as fat as onew who were
heavier.  The number of fat cells remains constant after puberty.
        I give my kids lots of fat, but...