Oh snap, I forgot one vital thing!
Ash is the boy and Amelia(Melly for sort).
Melly has a slight hint of pyromania, except she doesn't start the fires with matches all the time...sometimes she can do it with just her hand when she's really pissed off.
If you don't want the whole hand thing, I guess you could just forget the whole pyromania thing :]
Oh and Ash and Melly are twins so its like..double the touble with the whole disorders