DS had a slight accident a few nights ago and the matress was soaking despite protective sheeting (which obviously slipped!) Although I have sponged and scrubbed the matress as much as possible, there are no stains but it still stinks of wee. I've put bicarb on it (didn't work) and sprayed it with air freshener and perfume (getting desperate now) but it still smells really bad. Any suggestions about what to do next? Unfortunately taking it out to air in the garden isn't an option as we don't have one!