seeing is normal black tongue pigment. It can be striking, especially next to an almost identical dog with a solid pink tongue, but it is commonly harmless.
Keep an eye on shape, texture, and change over time. Flat and stable is reassuring. Raised, fast-changing, painful, or ulcerated means call the vet. But if this is one of those fresh-groomer photo surprises, there’s a very good chance the answer is delightfully boring: your sister’s Lab has freckles on her tongue.
