It not being Gabe's problem isn't good enough, and Johnny's about to say as much - it doesn't matter what Gabe said in the past, he refuses to believe that he would be angry over something outside of Seth's control, or let that anger overrule the desire to help his friend - but the rest of it stops him. He chews his lip; he can feel Nova's dissatisfaction, but she doesn't say anything either. Are Seth's powers more important than his health? Well, no, but Johnny's not in any position to say so.

"I'm not gonna tell him," he says, since it might bear repeating. "I mean, I was never planning on it, it's just - I just worry about you, man."

He's seen this before, been here before, and he knows where this can go. Even when you're being smart about it. Especially then, because it sneaks up on you all the better.