On a similar(ish) sort of note my 8 year old grandson triggered the alarm and required a pat down at DUS recently. His mum was still waiting to get through but I was with him. The security guy waved me on but I told him that I would observe (this from a distance of about 3 meters) whilst he performs his pat down. He again told me to move on and I again told him, sternly this time, that I would observe his pat down of my grandson - and if he didn't like it he was welcome to ask for a police officer to come over. Nothing more was said. I have no problem with security pat downs etc., however, for the benefit of ALL concerned security staff should not object to being observed by the parent/guardian/adult responsible for the child concerned.