I wanted to ask advice on my 3 ½ yr old girl. When she is sitting down on a hard chair or bench and concentrating on a task, she often starts wiggling her bum on the seat. It is accompanied by her holding her breath for a couple of seconds at a time and breathing deeply. In extreme cases, she goes rigid and can?t continue with her colouring, drawing or whatever she was doing. The nursery says that she is ?swimming?; a behaviour that can we found in girls and is a behaviour that gives comfort. However they have recommended that I talk to my health visitor about it. In all other ways, she is a bright, confident, chatty, happy child. Has anyone else come across this ?