Bowser

Certainly Klaus, Marjorie, and Howie Detterick did on the night the twins were taken. Klaus would almost certainly have been wakened by Bowser, the family's big old half-breed collie, if he had barked, but Bowser didn't. Not that night, not ever again. Klaus was up at first light to do the milking.

Detterick family collie killed during the abduction.