So yeah everyone knows Fred and George Weasley were born on 1st of April. Pretty obvious, right? Now take a look at what happens on that day...

*1st of April, 1985*

Seven years old Fred and George are awake already in their room.

Fred: Finally it's the best day in the whole year!

George: Our Birthday!

Fred: April Fools Day!

(Both of them looking at each other with meaningful glances)

George: What should we do this year?

Fred: We already pulled a prank on Old Muriel, she's so gonna love her mop of pink hair.

George: And last year we set fire to Bill's broomstick.

Fred: (correcting him) That was an accident.

George: How about we do something on Ronniekins?

Fred: Spiders down his trousers?

George: In his breakfast?

Both: His teddy bear!

Molly: (opening the door to check what all the noise is about) Kids, it's time for breakfast. And Happy Birthday, dears. Now hurry up and come down, your Dad's waiting.

After Molly is gone, both of them smile mischievously knowing the idea in each other's heads.

Fred and George: Oh yeah...

*At Breakfast*

Nobody could understand why there were gnomes in the Pudding, or why Ron was running around shrieking, or why Aunt Muriel had covered her head with a scarf and was muttering curses under her breath or...

Charlie: FRED GEORGE I TOLD YOU TO STAY AWAY FROM MY CUPBOARD!

Fred and George: (sheepishly) We didn't know dragon tooth was reactive to water. And we also had no idea that you collected dragon teeth.

Charlie: IT WASN'T WATER, IT'S ACID!

George: (whispering to Fred) Has anyone used the lavatory yet?

Percy: (with a boiling red face and glaring murderously at the twins) Now who put red chilli powder in the soap?

Fred and George: Happy Birthday to us, Happy April Fool's Day to you.

And let's just say that the chaos didn't end there, instead such antics continued all the way to dinner.