DS has been to a party at a soft play. Food was included. It was booked out so about half the parents stayed for coffee in the cafe. This is next to the room where the children eat.
One Mum there whos DS is in the other Yr 2 class, very much a helicopter parent. Spent most of the party trying to deal with non-existant problems, mainly children swinging an arm or running within 3 feet of her DS. Rest of us just chatted.
The party Mum knows DS has allergies and that he can't eat ketchup due to ingredients. Also party host informed and she says they wouldn't offer it if it would be a danger to DS. Tell her its fine as long as he doen't eat it.
In the party room (35 children around a large table)and the party hosts (employed by soft play) are in the room whilst party childs Mum wanders between party room and cafe - the parents of DC's stayed in the cafe. Fairly loud in the room. Helicopter mum enters party room and goes around squirting ketchup onto the childrens plates saying 'who wants sauce' Gets to DS and asks and goes to squirt it (before he answers) and DS realising it is ketchup shouted said in a slightly panicky way 'no, no, I'm not allowed that'.
A little had already landed on the plate.
The Heli mum replies 'oh its a party I'm sure just this once will be fine'. DS says 'no, I'm allergic to it'.
Heli Mum says 'allergic?, what to ketchup?, Don't be silly you can't be allergic to it.' DS says he is and asks for a different plate and is told surely he can just eat the food and leave it and tells him to stop making a fuss. 
DS starts to cry and pushes the plate away. At this time the party childs Mum says to Heli Mum he is allergic and goes to get him a fresh plate. She comes to me and says DS is upset.
I ask why and before she says anything the helicopter Mum (seeing party mum talking to me) storms over and tells me 'oh its all over ketchup, he wouldn't eat his food with it on the plate, said he's allergic'.
He is I said.
Heli Mum starts saying 'well I didn't know, I've never heard of the allergy'
The party childs mum apologised saying she hadn't said anything to the mum as hadn't seen or heard her come in and help. I said not a problem, probably my fault for staying in the cafe.
Heli mum started saying 'well thats true, I can't believe you left DS and risked his health, you all just sat there talking, I was the only one who came to check on the children, anything could have happened'. We were about 3m away FFS and the party hosts employed by soft play were there with the DC's 
I told her she was clearly an ignorant woman and should keep out of things she doesn't understand'.
Party childs mum says she's never invting heli mum DS again as the heli mum was a PITA. 
Oh dear IWBU wasn't I? Just annoyed me that heli mum wouldn't allow any child near her precious DS but practically calls my DS a liar - becuase she's never heard of it. 
AIBU though to now feel I don't want to leave my DS in case theres similar parents out there?