It didn't actually make the detector go off - not sure why I think they only go off at a certain amount of metal perhaps? I had CJ in the Ergo and in Oz they didn't even make me take her out of that (they did in the UK) - as she was only in the brace for nights at that point was only on the flight on the way out that she was actually wearing it through security. I doubt they would make you undress Bailey - I just said she is wearing a brace - but not sure if because of recent issues may have got more stringent again.