And I would've told the mother to tell the kid that... there are kinky women out there. And GGG women. And women who enjoy wearing latex. And that he'll be fine.
UPDATE: In all fairness to Prudence, people, I happen to agree 100% with the second half of this statement—well, I agree with the last word in the second half of this statement anyway: "While it can be difficult to fully extinguish a fetish, Kafka says behavioral therapy can make it less engulfing." Yes, it can be difficult to "fully extinguish a fetish"—it's can actually be what's know as "impossible"—and putting it that way irks me because it posits that there's something sad about this, i.e. that it would be better for all—for 13-year-old boys, for their mothers, for Prudence—if we could pry open the heads of 13-year-old boys, rip out their kinks, and reprogram them to only be interested in sex acts that meet with the approval of their mothers and their mothers' favored advice columnists. But I agree that fetishists—even at age 13—should be wary of becoming "engulfed" by their kinks; that is, they should be told that the goal isn't to extinguish their fetishes, but to incorporate them into their healthy and hopefully GGG adult sexual relationships. And if they want GGG partners to indulge them, they'll have to be GGG themselves, i.e. just as accommodating of their partners' desires—including their desires for vanilla sex.