my cat likes to sleep under thick covers, can she suffocate?

It's pretty hard to suffocate under covers. Your cat would have to be held down with the covers tight against her face for quite some time. Cats have well developed survival instincts. She's not going to suffocate on her own.

Mine don't like to be covered by heavy blankets, but some do. Don't worry, she will get out from under the covers when she feels like it. Some cats just like to feel burrowed, normal and safe.

Do you suffocate under the covers? If not, then she will be fine. =)

if you mean a real cat, yeah but mine do everynight and there allright.

No, if she can't breathe, she'll wriggle out pretty fast!