Here's one Drakin example, this one will come as an extra for the winner of this adopt: http://www.furaffinity.net/view/24694430/

As you can see, their features are influenced for the Candle Witch's own features, I prefer it this way as it'll show a more significant relationship between the Drakin and the Candle Witch that hatched them, but they can also look different from them (color scheme, traits, etc), the only condition is that their fire must match the one that was used to hatch them, even in color...unless, they're adopted, which may happen actually