When you have to be Serious!

Why is it always like this ;when you have to be serious something funny comes up?

Just like at school, when the teacher is trying to get student's attention on a non important subject, and your classmate is showing funny faces and saying funny words on back of the teacher, and you can't cotrol not to laugh...oh I miss those days!

Yesterday I was in the exact situation, when this friend of mine - from high school - was sitting exactly infront of me in a very serious meeting and I was trying to concentrate on the speach; but something strange is between old friends, you can easily laugh and loose concerntration by even seeing each other's face! and it happened! I was just trying not to look at her so that I can control my laugh, but just couldn't! I was lucky it happened at the end of the meeting so it didn't look that bad and looked like at the end it was pleasant!