I'm going to be very sincere. I don't ignore, I educate. So I *am* that parent who will politely, but very loudly will say something like, "I'm so sorry that my son's autism is triggering you, since you can't stop staring at us or you can't stop commenting about him. If you would like to find out about my son's autism, please feel free to ask me. I'll gladly educate you!"

I have never had anyone say anything to me or near me about my son…but I have RBF and that seems to make people uncomfortable 😆
But I was at a splash pad a few weeks back and my son was playing and I sat across the way. A family came in and noticed him stimming his hands and continued to stare at him as if something was wrong. Obviously they didn’t know who the parents were, but it was extremely rude. So I went and sat next to them
And continued to stare directly at them. They stopped staring at my son And after a few minutes they got up and left. I don’t give a f who you are. He is a child and if he stims he stims…learn some manners

As a retired RN who has a 3 year old autistic Grandchild I tend to ignore the ignorant. Engaging the rude can lead to disaster. ❤️

Unless the person is being very rude, I will politely educate them. Then maybe they will be kinder (or at least more patient) the next time they encounter a neurodivergent person.
I did once catch a woman mumbling under her breath when we were brought to a ride exit to get on a ride ahead of the line at Six Flags. I very quietly went to her and said "I'll be happy to trade places with you, but at least one of your children will need to become Autistic." It probably didn't change her outlook, but it sure did make me feel better.

At a grocery store, my daughter saw herself on a security tv screen.. so she was making gestures and dancing not realizing she was between the cash registers and exit. Now, my daughter was young enough appearing (though a teenager, 15) to get away with acting youthful however, an older woman with little patience decided that yelling at my daughter was her go-to response. I stepped away from the register and in between the two of them and made clear that "not all people with special needs are in wheelchairs. Practice patience".