would have to dig deep into the stew because the puppy was at the bottom

I am having a hard time getting that.
If puppy is more tender, it would be because its tissue is lighter and composed more of fat and areolar tissue than muscle and dense connective tissue. Then in a stew full of meat from multiple ages of dog and what not, the puppy should be more buoyant than the dog, making it float higher.
How then, does the puppy end up at the bottom?