We often act as if we're not little..and that's when we become sad.   We say yes to pride and not yes to humility.

Jesus told us - as each saint tells us - to come to him as "little children". 

Reminding others of what Jesus told us is no way being disrespectful to them.   It's actually helping them. 

Proud people are NEVER happy.   You can see them all over the place here.