Disclaimer: I don't own Harry Potter or Voltaire's "Happy Birthday (My Olde Friend)". Also, this ignores the fact that Dumbledore was actually born in July or August 1881. Instead, I say he was born in June of 1878.

Italics are the lyrics.

It was the 5th of June, 1978, and the morning began as usual. Everyone woke up, went to the Great Hall, and sat at their usual breakfast tables. Everything was perfectly mundane. Until a shout arose from the Gryffindor tables accompanied by furious gothic cabaret music.

"Grab the chair boys; we've got another bucket-kicker!"

The entire seventh year section of the Gryffindor table quickly stood, and they swarmed over to the Staff table, directly in front of Dumbledore. Out of nowhere, someone summoned the Headmaster, chair and all, to straight above the mass of singing bodies. He dropped, and was carried away towards a table with a large cake on it; a cake covered in so many candles that it must have been considered a fire hazard. Seemingly from the center of this swarm, yet from all around, the rest of the school could hear someone belting out a somewhat morbid tune.

"Happy birthday, my old friend! It seems this horror show will never end. Any moment's your last breath. Here is to another day closer to death."

For a split second, there was no singing, and out of the crowd came Sirius Black with a black guitar by his side, his face split by a manic grin. The teen was sporting a black beard and top hat, somehow previously unnoticed. He stood by Dumbledore's chair as it was placed in front of the cake. Then he started singing once again.

"The cake is on the table, and it is awfully bright 'cause there's so many candles on top. But you are so decrepit; your chest so tight; when you blow them out your lungs are gonna pop!"

At that, Sirius stuck a finger in his mouth and made a pop sound, which seemed to further amuse the little firsties, who were busting a gut at the performance already. Then he picked up the guitar resting on his hip and continued his song to the muted screams of his adoring crowd.

"You cannot complain each time you feel a pain; you have arthritis and gout. 'Cause when you start kvetchin' all your teeth fall out, so have another cigarette, have another beer! Raise your glass to one more year!"

"Gone!" was the answering shout from the rest of the seventh year Gryffs, dancing and moving to the music. To accompany it, they had thrown their hands in the air, creating a sea of fists for all of a second.

"Happy Birthday my old friend! It seems this horror show will never end. Any moment's your last breath. Here is to another day closer to death." The chorus made the cheering more enthusiastic, and Sirius was just eating up the attention. He had come up to put his arm around a still seated Dumbledore's shoulders and sway with the smiling man, whose smile, though cheerful, was shell-shocked. That would explain how he simply allowed himself to be tilted from side to side by the mischievous Gryffindor for the next two verses of his twisted birthday tribute.

"Your skin is so worn out and old; all over your body it's saggin'. Especially loose is your old caboose; you're dragging behind you in a wagon.

You're an alcoholic and you're blind and deaf and you have Alzheimer's I bet. You're too old to remember but you're too drunk to forget, so have another cigarette, have another beer! Raise your glass to one more year!"

Again came the answering shouts of "Gone!" and the sea of fists, just in time for Sirius to step onto the table and start playing his guitar again in earnest.

"Happy Birthday my old friend! It seems this horror show will never end. Any moment's your last breath. Here is to another day closer to death.

You're so old you smell like dust. Now your bones begin to rust. See that face, it's full of wrinkles. So have another cigarette, have another beer! Raise that chair to one more year!"

At this, Sirius threw his own fist in the air and everyone surrounding the Headmaster lifted his chair once more, prancing around the table with it. He bobbed and weaved as they carried him, clutching the arms of the chair with a grip that could've rivaled a pregnant woman's.

"Happy Birthday my old friend! It seems this horror show will never end. Any moment's your last breath. Here is to another day closer to death. Happy Birthday my old friend! It seems this horror show will never end. Any moment's your last breath. Here is to another day closer… To… Your… Sweet… Deeeeaaaath…!"

At the beginning of that second repetition, the crowd of 7th years carrying the Headmaster had brought him next to Sirius, still holding him in the air and dancing. The Marauder got near to the chair and started singing at the man, a wicked expression on his face as the song came to an end. As the final notes of the music faded, the spell on the audience was broken and the muted cheering was not so silent anymore. Dumbledore, for his part, blew out all of the candles on the cake before him in one breath.

"Thank you, dear boy, for this wonderful birthday celebration, but how on earth did you find out that it was my birthday?"

James stepped forward with Lily Evans in tow. "Actually, that part was Lily. She, being the sweet and innocent one, simply asked Professor McGonagall. It was way too easy. Happy Birthday, Headmaster. We're going to miss you when we graduate."

Sirius, flushed, sweating, and panting from his song, poked James in the side. "Oi, Jamesie, don't be so serious. Honestly… What this prat should have said was that you should consider this the Marauder's last hurrah at Hogwarts, since this marks the seventh year that they have been pranking the school, and they organized all of this. We can't really take the credit for that. But, hey, I completely made the song, don't you think?"

The whole audience laughed, and to end their ridiculous performance, the 7th year Gryffindors all called out "Happy 100th Birthday!" Remus, at least, had the grace to look slightly embarrassed by his compatriots' antics. It truly was Dumbledore's most memorable birthday.

Thank you for reading! I would love it if you reviewed, but be nice, please!