Hi Dan,
Watch carefully her response to Enbrel. There is another girl who had a transplant, Kayleigh, and her ANC took a big dive following Enbrel administration. You should definetely read her caringbridge site, might be very informative and a source of hope and comfort for Courtney. They are a very nice family, the girls might even like to correspond.
http://www.caringbridge.org/visit/kayleighinaz
All the best to Courtney and your family,
Sandra