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Our female JR is turning 14. She has a few physical problems (heart murmur, thyroid balance, arthritis) but still is as active as a puppy. Lately (she sleeps with us) she's starting waking up at 5am. She doesn't seem to have to go potty. Is there anything we can do to stop her from doing this? When she wakes up, it then wakes up our mini doxie, also sleeping with us.