my 5 year old has a severe learning disability ( possibly autistic ) is constantly chewing on things, shoelaces ( will just lift a shoe and chew the lace ) drawstrings on clothes, straps on schoolbag etc. have spoken to OT, and they have given him a rubber thing to chew on. Not making a difference, everytime i try to give it to him, he just says its the dogs toy, and throws it for the dog. Anyone else experienced this type of behaviour? Any ideas of what to do would be gladly welcomed.