One guest who didn't make it into J.C. Chasez's 40th birthday party? The grim reaper, whom Joey Fatone might as well have suggested was lingering around the event to make the former members of NSYNC — who reunited at the shindig — feel like they were quickly marching toward death's door.

Yesterday, Justin Timberlake shared a photo of the group's five members — who last released an album together in 2001 — from the Sunday (August 8) party. Fans couldn't believe how much time had passed ("Omg don't say he's 40. I still remember dancing to 'Bye Bye Bye' in my living room," one wrote), and Fatone told E! News NSYNC pretty much felt the same.

"Last night we felt like little kids," he said. "We were kind of reminiscing about stuff, but then all of a sudden it's like, 'Here's a picture of my two kids,' and Justin's like, 'Here's a picture of my little boy.' It's like, 'Oh, crap! We really are getting old, aren't we?' I never really feel it, though. That's the beauty of it."

"It's crazy," he added.

Still, don't expect an official reunion to follow. Fatone said the guys did sing "Happy Birthday" to Chasez, which — contrary to E!'s insistence — would not make a good recording, he noted.

"I think with the intoxication and the alcohol, I definitely would have sounded like crap," he said.

Consider this an official call for secret video/audio of the set.

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