To #sleep well and #safely, #babies need to be not too hot and not too cold.
Babies can overheat quickly if they wear hats or bonnets to bed. In fact, heat escapes through their heads and faces, so babies can only cool themselves down if their heads are uncovered. Keep your baby’s head uncovered in bed to make sure he stays around the right temperature. Also note that headwear in bed can be a choking hazard.