aaden -- oldest brother, more info soonish
austint -- twin, more info to come
aniala -- younger sister, more info soonish
gavint -- youngest brother, more info soonish
alexat -- youngest sister -- they are quite close, and Lyssa tends to explain away Alexa's behavior, most often blaming it on being the baby of the bunch.

Others:

azkadelliap -- AZ, as Lyssa calls her, is not only her childhood friend and roommate, but the keyboardist for Chaos Theory. They get on so famously, AZ is just as valued as a sibling. It's likely she understands Lyssa most.
meader -- Childhood friend, currently lives next door with an "open door policy".
jacksdane -- Lead guitar and vocals of Chaos Theory.  Lyssa respects his talent and tends to treat him as one of her siblings.