When I lived with my grandparents for awhile, after grandma died, grandpa asked me to stay for awhile. I got a job working 11-7. Everymorning I'd be home by 7:30, everymorning sitting at the back door with his ball was grandpa's dog. Grandpa said every morning at 7 the dog would go get the ball and run to the back door where he would sit there watching the door until I came home. Had grandpa not told me this I would have assumed the dog just heard me pull up and ran to that door. That's not the case at all.
Gracie is the best alarm clock, 7:30, breakfast! No sleeping in, everyone up! Now she's starting to act like she knows what time we take our evening walks. She'll bark at me to come, then take me to the front door. Every night at 9:30 she is ready for bed. They have a sense of time.