Hi and welcome to the Chiari forum.
Many of us have found it best to research NS's even once u find a Chiari specialist as u will want to compare them and go with the one u feel most comfortable with and ur child is with as well....we need to have confidence in our Dr in order to do well.
We do have a list of Drs in TX, I can't say which r ped drs...u will need to research...and I do not refer and the list is not a referral either just a means to give u a place to start looking....
U will find a list of Drs in the Health pages as well as other helpful info and tips -
http://www.medhelp.org/health_pages/list?cid=186