"Well as you've discovered, the Malfoy line has a specific gene. We don't know where it all started but your grandfather and his father both became animagi. As you know Abraxos died from Dragon pox, well he did - but they were a very rare form, only affecting actual dragons. The special part about the Malfoy Dragons is that they were the original creators of fiendfyre. Years ago, one of your ancestors was imprisoned and studied for his flame. Since then, everybody kept it hushed. I daresay you are the first to go on the ministries register - ever." Narcissa sipped her Champagne.