Jessica,
I have worked with several adoptive mothers.  The ones who were unlikely
to make any milk were the ones with tiny breasts and prolonged
infertility (no conceptions).  One recent mom was an exception to this
oft stated rule - she is now making about 5-8oz/day.  She pumped for 5
months before getting her baby, and worked up to a "tablespoon a week".
Baby latched on happily, mom used sns for a week and later, postcibum
bottles.  After a few weeks we calculated from baby's weight gain and abm
intake that she was producing somewhere around 8 oz a day.  Another mom
who had had multiple miscarriages (and had suckled her neice while
babysitting for her daily over the course of a few months) went on to
produce all the milk her adoptive baby needed.  Your mom sounds like she
has a really good shot at producing significant quantities of milk.  Of
course there are other important reasons to nurse adopted babies-
closeness, oral motor development, bonding, even if there is no milk
produced.
Catherine Watson Genna, IBCLC  NYC  [log in to unmask]