Had one of these parents in regards to my PG son. She would be right in my face with questions like "what is he doing, what do you do to get him to do all this". I would try to back up but to get some space but she would back up right along with me....horrible. Wherever I went she would follow. I did have to tell her what DS was doing, because she would not back off until I did. I ended up just saying that he does it on his own terms with little involvement from me. This seemed to work. I mean, what can you say to this? I have no "tips". End of discussion.