Melody Pond was special. Yes, it is true, but not for the reasons they had thought. Her conception aboard the TARDIS was not the causal nexus of her "Time Lord genetics". It was due to her maternal mother. Amy Pond had had the universe poring through her dreams and mind from a young age. Her developing years were profoundly affected by her constant exposure to the universe. Her exposure mimicked the early developmental traits similar to those of the Time Lords; who had adapted due to their time travel and exposure to the universe. Despite the second Big Bang the changes, on a molecular level, were permanent. Later, when Melody was conceived those genetic traits were passed on. Amy aged and appeared on the surface to be an ordinary human, but her unique traits were only activated in death situations. The Doctor had left her and Rory on the doorstep of their townhouse. It had been years since the TARDIS adventures. Amy had aged and loved completely. Despite the opportunity she and Rory had decided to not have another child. Ten years later, with a successful modeling career and perfume line, the impossible occurred and nothing would ever be the same.