This happened last month on my 16th birthday. I came home after dinner with my mom. When we got to the door, she said "I have a surprise for you"!
She put a blindfold on me, and led me to the dining room table. Just as I sat down, the phone rang. Mom went to the hallway to talk. I started feeling my stomach rumble, so I let out a loud fart. It was nasty. Then another. Then a looooong one, which smelled worse than anything. A minute later, mom came in and said "SURPRISE" and took off the blindfold. All my family and some friends were there.
My cousin Dave looked at the cake and said "maybe it should say Happy birthday...you big stinker!"
I was really embarrassed!