The Brotherly Bully

I’m the oldest of three siblings, and I love playing pranks on my little brother. We had this one stuffed animal that he loved to death, and one day when he was over at a friend’s house for a sleepover, I took it and hid it under my bed with a note saying 'From your secret admirer.' Of course, as soon as the shock wore off, he got furious. Now every time we joke around about something missing, it always circles back to that night. Is this normal sibling rivalry or am I just an over-the-top prankster? Should I stop being such a bully?