English idioms: to have a skeleton in the cupboard

Hi!

Since it's Halloween, I've decided to find an English idiom on the theme.

A cupboard is a synonym for closet. It is the place where you put away your clothes, or books, or toys, etc.

"Skeleton" is a transparent word, it is the bone structure of the body.

To have a skeleton in the cupboard means that you have an embarrassing secret, that you are hiding something.