She has a silent purr, but her eyes roll back in her head when you pet her. These are the coolest cats ever when they're not attacking your freshly bathed naked children as prey. The sort of 'trill' like a raccoon when they are excited, such as spotting a squirrel or bird.
Our smaller kitten, Jessie seems to be learning this unusual trait as she stalked a fly this afternoon chattering at it. She is a lover and will lick your nose with her sharp sand-paper tongue. We always hear her before we see her, because she has an extremely loud purr.