I have seen sophie lay like that...and she is supposed to be 3 yrs old. Piggy the frenchie lays like that as well, when she does her snoring wakes up the whole house! Piggy is supposed to be 5 yrs old...but I think that is a bully breed thing.
Casey our spoo puppy stopped laying like that at about 6 months old. She will roll over like that to stretch, but won't sleep like that!
Doesn't he looked relaxed and comfortable too LOL. Gorgeous. T will still sleep like that at times but he's not quite 7 months yet, it is certainly getting less and less that he does it though. Hmmm not going to be a puppy for much longer DOH!