See here.
Dany, Maegor, and Rhaenyra all had what sound like half-dragon deformities in their newborns. Is there any pattern to be found among them? Dany’s son Rhaego seems to be the victim of magic, and Maegor’s children might have been too (either from Tyanna or Maegor’s own potentially magical conception). But there doesn’t seem to be magic involved in Rhaeyra’s stillborn daughter. Is there anything in common at all?
See here.