What is turn that frown upside down?

"Turn that frown upside down" is an idiom or a phrase that means to change a negative or unhappy expression into a positive and cheerful one. It is a way to encourage someone who is feeling down or sad to change their mood and attitude into a happier one. The phrase may have origins in a smiley face created by Harvey Ross Ball in 1963 that became a symbol of happiness and positivity. The phrase is commonly used as a form of motivation or encouragement in various situations, such as to cheer up a friend, to motivate oneself, or to create a positive atmosphere in a workplace.