Most professionals are really trying to help your child. It's okay to disagree, express emotion, cry or be angry. In many cases, that might be the right approach, but I don't think it would work for my child because . . . You may disagree with professionals about their recommendations for your child. Don't be afraid to say so.
Professionals are only human.
Sometimes they are mistaken. You know your child in a way they can't. Based on your input, professionals may change their recommendations. I still don't understand why you think that . If you don't understand how the professional came to a conclusion, ask for the specific reasons behind it.