We have a Cocker Spaniel whos 8 years old. Its weird but she keeps on having dreams

. She will lie down and fall asleep and then all of a sudden she will start barking or growling etc in her sleep. And today she was asleep laid down and then woke up and started howling laid down . Is this normal for a dog to do this? Does your dog do this?
I find it all amusing though haha!

