Babies that are under 18 months of age cannot and should never sleep on blankets.
Because the baby that is under 18 months of age might roll over onto the blanket face first and then suffocate and not be able to breathe.
You should always wait until the baby is at least 18 months of age or older to give them blankets to sleep on or under and also wait until the baby is 18 months of age or older to put stuffed animals, pillows or any other soft objects in the crib or bed with the baby.
It's also recommended to keep the baby in the parents room until they are at least 18 months of age so that you can be close to the baby and tend to it's needs more easily.
After the baby gets to 18 months and above you can move them to their own bedroom.