Blankets are unsafe to leave in your baby's crib, so it's important to find alternatives for when your baby needs to be kept warm. Layering clothing is a good method, as if your baby seems too warm you can easily remove a layer. Try dressing your baby in pyjamas or a bodysuit, in addition to their swaddle, wearable blanket, or sleep sack. Ensure you check the TOG level of your baby's clothes to ensure they won't overheat.