Glad she's doing well and I wish her all the very best.
But I've just seen this on Facebook:
Er, what worthy cause? She was/is treated by the NHS, if there was a charity involved fair enough, but where will the profits from this go, straight into the pockets of her family? What, just in case they can't get enough out of Merlin, they want to cash in from the general public too?
Whilst the gig is a nice gesture to show support for the girl, the family should definitely be donating every last penny raised by this to a deserving charity. If it does turn out to be Merlin's fault, they'll be compensated accordingly, keeping the profit from this just makes them look greedy.