I think it's fair enough for the nursery to keep a closer eye on this to make sure it doesn't happen again, but at that age it wouldn't particularly worry me. Probably a good time to teach your son about private areas and not doing something he doesn't want to do just because he's been told to.
Mmm Not sure, it could be just a phase he is going through but I would have a word with the nursery people just for them to keep a watch out. Why would his willy have been exposed anyway? (maybe they were going to the toilet or something?)
You need to tell the setting, and ask them to explain how they will deal with it. (And then check they do).
Also, leave it to the setting to determine if there are CP issues here (someone there will have the relevant training and more knowledge of the child in question). I wouldn't be worried based on information in OP as willie obsession is very common, and "kiss my ass" is probably just a bottom joke.
my partners step dad said that my 5 year old son said to him kiss my willy and balls and was laughing hysterically about it.
im not worried about it, we dont use the word balls at home so i know he will have got it from the boys at school and their older siblings. im not concerned because since starting reception he has spoken about his willy and how it tingles sometimes and i can see that this kiss my willy is just a development of discussion and that he dousnt really know whats wrong with kiss it.
I think if this has happened completly out of the blue and hes never been intrested in his willy or he seems upset then maybe worry but if not he probebly just hasnt worked out whats appropriate and we all know kids of that age have no "shame".
i just told my lo, no we dont do that, your willy is a private thing and other people dont want to see it.