Sara,
        Yes, babies with Down Syndrome grow MUCH more slowly than regular
babies, but with lots of variation, too, depending in part of size and
growth patterns of parents and siblings.  My son Peter was 3 weeks early (6#
7 oz.) and had intestinal problems requiring surgery.  He was up to 12
pounds by 2.5 months (mostly breast milk, but we did supplement with ABM to
get him up to the 12 pounds more quickly in order to have the stomach tube
removed).  One also worries about heart defects in these babies -- I assume
baby has been checked thoroughly for heart defects, but this could cause
slow growth also.  Yes, many babies have trouble with chewing and digesting
solids.  Aside from pureed baby food begun at 6 months, Peter would only eat
apple-raisin-oatmeal cookies until he was almost 2 years old.  That is to
say, he refused to "chew" anything else.  There are special Down Syndrome
growth charts, first author is Chris Cronk, published in 1988 or there
abouts.  I can send a copy by snail mail if doctor is not aware and doesn't
know how to find them.  If mother wants to talk to a growth specialist with
a 10 year old with Down Syndrome, tell her I'd be happy to chat.  Peter now
weighs about 65 pounds, and is 4.5 feet tall.  That is to say, quite short
for a 10 year old, but proportionate weight for height.  The big worry for
children with Down Syndrome is not that they grow too slowly, but that they
get too fat -- both due to slower than usual metabolism, and to lack of
exercise due to poor coordination, lack of opportunities to play with other
kids, etc.  However, Challengers Little League starts soon (fun baseball for
kids with mental and physical handicaps).  I would be more concerned with
"how do I keep this kid from becoming overweight early in life" than how to
make the baby grow faster.  Hope this has been helpful.

Kathy Dettwyler, Ph.D., specialist in infant/child feeding and
growth/health, and Peter's mom (also Miranda and Alexander's mom)