Since cetaceans are mammals, they have hair at some point in their life! dolphins are no exception. Dolphins have a few whiskers around their snout in the womb and when they are first born but they soon lose them.

Amazon River dolphins (botos) keep these hairs into adulthood - they are sensory hairs and thought to help them search for prey on the river bed along with echolocation. The water they live in is very murky so eyesight has only limited use.

The bumps on humpback whales’ head, mouth and even on their flippers are called tubercles. Those raised surfaces are actually hair follicles where a single hair grows. Similar to like a whisker, it helps the whales be able to sense their environment.

https://us.whales.org/do-whales-and-dolphin-have-hair/

Y’all just can’t let a woman be right, can you?

They’re born with hair and it falls off.