Board Thread:Lore Discussion/@comment-6702118-20140722142914/@comment-5029114-20140731114253

Think of it this way;

Akatosh and Alduin are two sides of the same coin. Alduin is the Firstborn of Akatosh, but not in the way you would think. Akatosh didn't directly make Alduin and the Dragonborn bloodline just so they could fight eachother.