The Fire Dragon Goddess

Hadley is the first born daughter of Hades and Maleficent but it was quickly apparent to the villain couple that Hadley was more like her father then the evil fairy and with Maleficent wanting a kid that was just like her it meant that the couple had another kid and that is how Mal was born who was exactly like her mother this caused Hadley and Maleficent to grow estranged.
Mal and Hadley were really close and often tore up the island together along with Evie the daughter of the Evil Queen, Jay the son of Jafar and Carlos the son of Cruella De Vil and together they formed the baddest gang on the Isle of the Lost although there was a few people who'd argue that. Uma the daughter of Ursula and Harry the son of Captain Hook which formed the leaders of the other rival gang on the Isle and despite relationships being rare...almost nonexistent there was a forbidden dalliance between Hadley and the First Mate of Uma's Gang.