I'm the youngest of 3 brothers, but there's enough of an age difference that I escaped the worst of being pranked by my brothers; mostly that was done by oldest brother to middle brother.

The one I remember done to me was my parents going out for the evening leaving my brothers to take care of me. They fed me a glass of apple juice and after I had gulped it down, convinced me it was made out of worms that they'd found in a pile of dog shit and blended up in the blender. I flipped out, got my revenge by barfing on middle brother's shoes.

Bro #1 didn't so much prank Bro #2 as just flat out abuse him. The story Bro #2 still tells is how Bro #1 chased him down, sat on his chest and pinned Bro #2's arms down with Bro #1's knees, then Bro #1 plucked a couple hairs out of Bro #2's head and tickled Bro #2's nose with them, while taunting him saying "it itches doesn't it, and you want to scratch it so badly, but you can't...."