It is best if nobody smokes in the house, including visitors. Anyone who wishes to smoke should go outside. Do not take your baby into smoky places. If you are a smoker, sharing a bed with your baby increases the risk of cot death. Overheating can increase the risk of cot death.
Babies can overheat because of too much bedding or clothing, or because the room is too hot.
Remember, a folded blanket counts as two blankets. When you check your baby, if he or she is sweating or the tummy feels hot to touch, take off some of the bedding. Don't worry if baby's hands or feet feel cool, this is normal. It is easier to adjust for the temperature with changes of lightweight blankets. Babies do not need hot rooms, all night heating is rarely necessary.