Just as white privilege exists and male privilege exists, facial privilege also exists. Thank you for recognizing that there is nothing to apologize for.
Yes, people grow and learn and at different rates. There are many learning styles as well and as you pointed out some must actually experience and then reflect.
As for reacting inappropriately upon seeing a child or any individual with signs of NF, if a child is 3rd grade or older they need to be talked to about the inappropriate behavior. Look at it this way, would society tolerate anyone older than 8 years old screaming monster if the child saw a person of color?
Your father reminds me of Mr. Monk. Even adults need to be educated. There was a thread or two about a family who took their daughter who was also facially different. She had what appeared to be a rash and the family was treated very rudely by patron in the restaurant. Some DUers sided with the family while others said the patrons were correct in asking management to ask if the child was contagious. Point being - Just Ask. That last sentence is not directed to you personally, it is for anyone who has bothered to read this far.
First we do need to take care of our LGBT family and the rights of women to control their body. But maybe in the year 2525 (if man is still alive - an attempt at humor here) those who look like the Elephant Man (not NF), Reggie Bibbs (African American with NF -Google his name) and everyone else who has genetic disorders will have their rights, too.
AC, now I do apologize for this rant. I am just hoping one day a celebrity (besides Gillian Anderson) will speak up and let society know (or to use your words, point out) that tumors are not contagious.