Lila, my 4month netherland dwarf was in her cage because it was bedtime. My boyfriend and were still watching television and not really paying much attention to her when out of the blue she squeaked. Of course I went flying to see if she was okay when I found her still fast asleep on her blankie. She woke up looked at me and went to her litter box, she is still eating normally, playing and she has not made that noise again so I am starting to think she was just dreaming.

Do any of your buns make noises while they are asleep?

Yes, mine make noises. Hannah will sometimes make soft squeaks rhythmically while she breathes - kind of like a person snoring, but more of a squeaking sound.

Otto doesn't make noise, but he will make chewing motions and twitch his eyebrows around when he's in a deep sleep.

I've only seen Rupert sleep a handful of times, but I do think I recall like Elrohwen described-a soft squeaky breathing noise. It certainly sounds like your bunny was dreaming

I'm certain bunnies, and all animals, dream. I've never heard my buns squeak while sleeping, but Bindi, my lop, often makes little moaning sounds and chewing motions. I think he's dreaming of food when he does those!