Jwdym

Alright, so this is kinda weird and all, but stick with me and maybe I can explain myself. I'm almost full-blooded Irish, and I LOVE the myths and legends and stories from Ireland. I also love Greek mythology, but that's besides the point. Anyway, on to the story....
The girls' mother was Morrigan, a goddess of the Tuatha De Danaan. (the immortal fairy/deities of ancient Ireland)Except for Mina, they all have extremely powerful magickal powers, great strength, immortality and lots of nifty other powers. Such as: being able to control the elements, speak with animals, kill things/people with a thought and lots of other stuff I haven't figured out yet. The girls are also older than Spike (176)and Angel (257) {those are just ages I made for my AU storyline. I think Angel's is pretty accurate, but I know Spike's is off by at least 30 years.} ANYWAY:
Rhianna is eldest, she's 572
Mara is next, she's 571 (Mara is more powerful than Rhianna)
Kayla is 562 (they're twins)
Leila is 562 (they're twins)
Lana is 557
Kiara is 555
Mina is 502

Mina is their adopted sister and barely has any power. Her parents died in a battle between the Tuatha De Danaan and the Dark People. They were just servants, but when they died, Morrigan took Mina as her own child and tried to cultivate her power, but Mina just wasn't strong enough. However, she has a big heart and is willing to do anything for those she cares about.

When Morrigan died by poisoning, betrayal and beheading, she passed her strength and energy to her best student, Mara. Rhianna was always not as eager to learn and didn't care much for anything but books, so she gladly let her slightly younger sister take the Legacy.

Only very few things can kill this type of immortal:
1. A poison called Fera Meta Chlorophine (made that name up)
2. Beheading and removing the head far away (kinda like the Judge from BTVS, but not as nasty)
3. a magickal daggar called Nahhiar Macushala