DS (8m) is all hot and grumpy having woken up from his sleep in his bedroom which is 25 degrees, 4 degrees hotter than downstairs. His room gets baking and I think we really do need to get something to cool it down.Can anyone give me any advice on those air cooler things (you put cold water of ice in or something like that) and also portable air conditioning units ? How noisy are they when they are on and do those air cooler things actually work or should we get an air conditioner ? TIA