Yeah, they're pretty amazing. I've seen other vids of them (they sometimes bill as The Stella Sisters), this is the first I've seen this one, though.
They're both good but the little one is going to be something some day. I've seen one or two vids where it's kind of obvious that she's the one with better vocal control and wider range, which is pretty amazing at her age no matter how much training she may have had.
Love love love them too. I am very impressed with them both and although I hate pointing out that one is better than another because they are a group I would have to agree. They have a very talented family and mom and dad are awesome too. Lennon and Maisy's ring of fire is the version I listened to when I did this song.