Family Tree or Lineage

I think it would be even more immersive if you could build a bloodline, family tree, or lineage that can be tracked for different characters. This would allow for players and NPCs to be multi-racial.

A Draconic-Sorcerer would be able to see which family member was a dragon and it could apply to other characters that are effected by class and race.
You could also make it optional for a character to be aware or know of their lineage, even learn about it as they go through the campaign. They could even meet relatives that get added on to the tree.
You would be able to build it from scratch manually, or you could create it organically through your adventures.

There is also possibility for inheriting abilities, curses, diseases, etc.

I just think it would be really cool.