Rose,

When MooShoo was a baby, he did the exact same thing. How he ever contorted his body in order to do this is beyond me. But, every night after settling under the covers to sleep, all I'd hear is this sucking noise. At first it was loud. As Moo fell into a deep slumber, it would stop, meaning he was sound asleep.

He did this till he was well over 2 years old. Now I think it's because he's just too fat and can't reach.