Peter considered it, and shrugged. "I don't know. If anything, my blood might be diluted by half a dozen other things. But it was still potent enough to revive Buffy after she'd been turned into a vampire. If it was strong enough for that, but it can't help..."
Peter was just as tense, if not moreso, as his brother. He was both furious and terrified at the thought that Mantis wouldn't be around. He needed the telepath - Peter loved him like family. He couldn't sit around and just wait for this to happen.