A.,
My daughter was born with Transposition of the Great Arteries, multiple VSDs and Pulmonary Stenosis so we have had a little experience with heart surgeries and procedures. However, we went to Children's in Dallas so I can only speak of our experience there. My daughter had surgery at 1 day old, 6 months old and then Open Heart surgery at 8 years old. She also had a couple of heart caths in between. She is now 17 and doing well but her heart is definitely not like a normal persons. I would be willing to talk to your friend if she just wants to connect with someone who has been through something similar. I know how much I appreciated being able to talk to other parents.
I also have a friend whose daughter has different major heart defects that may be more like your friend's son and I'm sure she would be open to talking about her experiences also. They had most of their daughter's procedures done in the Boston area and so probably cannot help with info on the doctors at Cooks since they now go to Children's in Dallas.
Children's Dallas also had a group called Heart to Heart that is a good support group for families. Maybe Cooks has something like this also. Please contact me if your friend would like to talk and pass on our prayers for her family.