Barking mad...

There’s a Swiss-German couple staying at the hostel. They speak German. Their dog speaks English.
(Well, they speak to it in English and it seems to understand what they want him to do, anyway.)
I ask if it is because it is an English breed. They look at me as if I am a bit loopy, or dim, or both.
“Of course not! It is because our other dog speaks English, too.”