Status: TBD
This hasn’t been confirmed or ruled out yet!
Original Theory: It sounds far-fetched, but the theory that Tyrion Lannister is actually Daenerys's half-brother — the bastard son of the Mad King Aerys and Joanna Lannister, who died birthing him — is actually quite popular. In the books, he has white hair (a Targaryen trait) and an early fascination with dragons, and a history of intermarrying within the Targaryen bloodline often led to physical consequences (like, theory-believers assert, Tyrion's dwarfism) when having children. If Tyrion is indeed on the receiving end of a dragonfire blast during season six, there's a chance he could emerge unscathed and really shake things up as a Targaryen.
