What age did you

Give your baby a blanket to sleep with? My daughter is just a few weeks shy of being one. She’s now waking up in the middle of the night cold, even with footy pj on. I live in northern Michigan so it is cold especially at night. I’m debating on putting a thin/small blanket in with her at night but she rolls at lot so I’m afraid, also she was born 6weeks early and had breathing problems