Why your pet drinks water strangely — and when to worry.

Pets drink water in ways that seem peculiar to us and are rarely peculiar to them. A cat who will ignore a freshly-filled bowl but drink enthusiastically from the bathroom sink. A dog who will only drink from the toilet. A cat who paws at the surface of the water before drinking. A dog who laps once, pauses, then starts again.

Most of these are normal, explainable, and not cause for concern. A few are not.

Here is a guide to telling them apart — what's a quirk, what's a preference, and what's worth raising at the next vet visit.