Why is it impossible for me to get a second opinion for my child.?

I have a five year old daughter with unicuspid aortic valve stenosis which requires careful prep. for surgery. Her ent has suggested putting tubes in ears for a second time. This doctor has been very hateful with me since my daughter had a rebleed from a T&A surgery six months ago. My daughter had to be rushed by ambulance to the nearest hospital, and she was throwing up so much blood she ended up with a blood transfusion. Five hours later after ER staff got so upset they called her and told her to get there right away (her office is only one block from hospital) as they had called her several times. Now I feel I should get a second opinion before she performs surgery on my daughter. But since I have a state medical card for her, they are telling me they won't pay for one. Can anyone give me any advice as to what to do?