How can a lion who has huge fangs carry their babies by biting them in the neck and doesn't hurt them?

Nobody has really shown yet why this works. So here goes.

Here is a lioness

Pretty badass teeth. And here's one carrying a cub

Same teeth. Now the lion cub is completely relaxed. Not a single muscle is used here. The lion here is not closing her mouth completely, like in the first picture. It's more like this, slightly open

It is commonly applied when describing people who suddenly claim to be something different than they once were. I’ve mainly heard it in reference to someone who has a history of lying or cheating. “Once a cheater always a cheater.”

But as we move closer to the ground level, we can look at Tigers who have been domesticated.

(sidenote—wild tigers groom themselves just like housecats. Although I doubt they lick their own crotch on the dining room table like cats do.)

Occasionally, people say a Tiger “went crazy” and mauled one of the zookeepers.

it is a total misuse of the term crazy. A tiger was doing exactly as the tiger was meant to do. The tiger went tigee.

Don’t act like the Tiger was crazy, perhaps, the human was crazy. It would be far more applicable.

But let’s zoom in a little closer.

A tiger is truly committed to being what it is, to the point that it literally can never lose its stripes.

Why?

Because those stripes are on its skin as well.

All the bones of the lion cub fit perfectly in there without being put under pressure by the teeth. And the relaxed muscles mean that the skin and fur can move around freely, draping around the teeth. It's more like a gate holding the cub in place. The larger fangs stop the cub from falling out.