When is it safe to use a comforter? I have one of those dinosaur blanket ones. Not made out of a breathable material. Is that ok from 6 months to sleep with? Thanks!

Red Nose recommends that you keep soft toys &/or comforters out of babies sleep environment until at least 7 months of age, as they may cover face & risk suffocation.
This is the age that babies will start to develop an attachment for transitional objects that may be of comfort to baby when separated from parents or caregivers.
https://rednose.org.au/article/soft-toys-in-the-cot

Red Nose does not recommend any specific products or material types for comforters.
However, it is important not to use one that is large (& may cover baby’s face) or with objects (like beads) attached to it which may become loose or products that have small buttons in them that a child may swallow or choke on.
Also, ensure there are no strings or cords that may wrap around baby’s neck, creating a risk for strangulation.

Red Nose also says:
Keep the cot free of large soft toys, pillows, bumpers, activity centres and anything else that could be ‘stacked’ to assist a young child/toddler to climb out of the cot.
https://rednose.org.au/article/can-my-baby-have-a-soft-toy