Dried Ghasts in lava become normal. Happy ghasts could be blue inside

The Minecraft live said that happy ghasts could have different physical makeup that makes them lose their fire abilities, so what if we take that and put it in the opposite direction for world building? If a dried ghast is placed in lava, it grows to be filled with fire and eventually becomes a normal ghast, possibly tamable but who knows. Happy ghasts could also become blue inside to show the differences in form