These days, it's kind of impossible to talk about 5 Seconds of Summer or Good Charlotte without mentioning the other. If it wasn't for Benji and Joel Madden, it's hard to believe 5SOS would've released the two kickass albums they have, and if it wasn't for the Aussie lads, it's hard to believe GC would've ever reunited. We're, like, really freakin' lucky they're buds.

Anyway, you might've read our complete guide to 5 Seconds of Summer's first LP and noticed that the Maddens are responsible for co-writing a handful of the songs. They penned all of "Amnesia," and we're better because of it. 

Last night while on The Voice Australia, Benji and Joel rocked through a performance of the slow-burning ballad, watch it above.

It's hard to consider the song a cover because, you know, they wrote the thing, but still...it's a rare gift to see the Madden Brothers tackle the tune!

When you're done memorizing every second of the clip, take our quizzes: Which Good Charlotte Song Best Describes Your Life? and Which Member of 5 Seconds of Summer Are You? Then watch Good Charlotte tell Fuse about their decision to reunite: