Can you say that human, whale, and bat might belong to a common ancestral group?

Humans, whales and bats have one thing in common: they're all mammals. This means that they have a common ancestor that is not shared by for example fish: in this way, they can be said to have a common ancestor, the first mammal.

However, in the end, all life on earth can be trade to a common ancestor - so to some degree this can also be said about all animals.