Both Newt's tone and the look he shoots Sirius then are pointed. Sirius's eyes narrow a moment before he lets out a huff of assent. "Yes, fine," he says, rolling his eyes. "It's just-- Is there any way of picking things up a bit now? His symptoms are getting worse, not better. What if there comes a day where he doesn't stop bleeding at all? Or his memory leaves him completely? What if he's just-- What if he--"

Sirius can't quite bring himself to say it, can't voice the fact that Kieren could die. Well and truly. Again and for good this time. That this condition, whatever it is, could win.

"Maybe there's something I can do to help," he says instead, feeling a bit more frantic now. "I don't understand any more about your Muggle science than you do magic, but perhaps we could work together. A spell that could work with these blood samples, a charm to alter it somehow. Anything at all."