An old problem, but either is re-appearing or wasn't fixed.
My 5 year old daughter loves to play, and her latest love is the tamed dog.
Her greatest frustration, however, is that her pet dog will not un-sit.
She's tried right-clicking with hand, bone, beef, hitting it, pouring water on it.
This is in creative mode. The dog tends to be in a tight area (blocks or chests, etc. around it except for a couple sides. She pushes the dog to move it around. It barks and shows love just fine, and exiting and re-loading does not fix it.
Recommended fix: as this is a recurring problem, and could either be in the use-item code or dog logic, I would recommend changing the dog right-click logic to have an option button like on the pocket edition. Further, because this is a child's delight, I would recommend extending this button to provide more behavior's. Sit, stay, guard, follow, play, hunt, etc.