The blond twin has some crazy, internal alarm that goes off about 6:30 a.m. every morning. We finally told her that she had to stay in bed until 7:00 a.m. on weekends. To her credit, she does wait until 7:00 a.m. to come into our room on weekends to wake-up her still-tired parents.
Then, out of nowhere, she slept in until 7:30 a.m. Of course, we were awake and waiting for her to come into our room. At the same time, we enjoyed the extra peace and quiet until the back-up alarm went off.
It turns out that Oreo also has an internal alarm clock. Shortly after 7:00 a.m., he howled for a minute as if to remind us that he was there. When we didn't come downstairs, he stopped. We had another short howl a bit later. Around 7:40 a.m., he really started howling. He wanted some attention and wasn't interested in waiting for us anymore.
Now we know that if the little blond alarm clock doesn't go off, the black and white canine version will.