Slightly odd

Apparently, my puppy has no bones.

Jack is forever just collapsing. He just slid off the big chair on which he was dozing and landed in a heap, apparently without even waking up.

This is turning into an amusing regularity. Rub his ears, and his legs go out from under him, then he's on the floor. The gals at the vet stroked him, and he just flopped down. He was sitting on my lap earlier, nodded off, and slipped to the floor.

Is this a lab thing? Will he grow bones as he gets older, or am I doomed to have a collapsing dog for the next ten or 12 years?

NOTE: It's not a submissive thing, it's some sort of...laziness/mellow thing.