The dog at Grindley Brook lives at the café at the bottom of the staircase. He/she likes to run up and down the locks chasing and retrieving a toy plastic spanner. The toy is put at your feet, and then you are expected to throw it for the dog to fetch. I didn't find out the dog's name.*
*(edit) Thanks to Andrew Denny I can now give the dog a
And, just to make it clear, Bee doesn't (necessarily) live at the bottom of the café's staircase. The café is at the bottom of the staircase locks.