I second thefreeaccount's observation. Please rethink keeping your letter posted. I was very moved by your letter to your doctor; however, I used to work for a Doctor who would do that very thing.
He was a cancer specialist, and because he would recommend one form of treatment and the patient would choose an alternative treatment, sometimes the patient would have an adverse reaction. The patient and sometimes their family members would then blame the doctor, saying he didn't warn them about the dangers, etc, and would sue for compensation.The first thing the lawyers for the Doctor would do is subpoena the letters, emails, phone calls etc of the patient to the doctor, to use against them in court. Also, isurance companies use these methods as well. I'd hate to see that happen to anyone here.
Please don't misunderstand me-I totally support and understand your seeking alternative treatments for your son, and we all appreciate reading the updates. I just want to inform you that this particular letter might come back to bite you later. Best wishes on your son's treatment; be sure to update us on his condition.