Cathy's post about her experience with her slow gaining son mimics mine.
At 4 months Jesse's weight gain slowed and at a year Jesse weighed 14 lbs
(7 lb 14 oz at birth).  He continued to be off the bottom of the chart and
the smallest kid in his class until he hit puberty.  Now he is the same
size as his dad and premature older brother ( 4lb 8 oz at birth, 20 lbs at
a year): 5 ft 7 in and 135 - 145 lbs.  Then there is my third son: same
size as Jesse at birth but at 15 years a giant among us (my two daughters
and I are 5 ft 2 in) at 5 ft 10 in and 150 lb.  My concerns with Jesse's
weight were offset by a physician who looked at the whole child, the
parents' stature and truly believed in breastmilk.  I agree that failure to
thrive is still used too widely ( I so vividly recall Kittie Franz
presenting at the 1980 LLLI conference in Chicago defining failure to
thrive and how positioning  can affect intake and knowing Jesse no longer
deserved that label!).  So, before labeling, figure out exactly what it is:
failure to thrive, slow weight gain, inadequate weight gain, or is it
appropriate weight gain that does not look good on the chart.
Linda Beckler, RN, BSN, IBCLC
Mandan, ND
"Be resolutely and faithfully what you are; be humbly what you aspire to
be."   Thoreau