Provided you follow the guidelines on your nursery thermometer (provided FREE with 0-6 and 6-18 month Grobag Baby Sleep Bags), there should be no danger of your baby over-heating. Always keep your baby’s head uncovered. It is safest to use a Baby Sleep Bag without sleeves and never use any clothing or bedding with a hood attached. Decrease the level of nightclothes and bedding if your baby is unwell and has a raised temperature. If you are in any doubt, please consult a Health Professional.