In my headcanon, Cory cloned Shawn but as a girl so his daughter could have a Shawn in her life.
Because the human body regrows cells we technically get a body every ten years.
We regenerate every ten years.
We are Time Lords.
We all change. When you think about it, we’re all different people all through our lives, and that’s okay, that’s good, you gotta keep moving, so long as you remember all people that you used to be. I will not forget one line of this. Not one day. I swear. I will always remember when the Doctor was me.
The 11th Doctor (The Time Of The Doctor)