Carrie Underwood and her husband, Nashville Predator Mike Fisher, are showing their support for an important cause.

The country music superstar and her husband joined in with Tennessee Senator Bob Corker to show people how to take part in the End It Movement for Shine a Light on Slavery Day, which takes place on Friday (Feb. 27). They posed for a pic that Corker posted in a tweet, with each of them sporting a red X on one hand.

According to its website, the End It Movement is "a coalition of the leading organizations in the world in the fight for freedom. Our amazing coalition partners are doing the work, on the ground, everyday, to bring awareness, prevention, rescue and restoration."

The group's statistics estimate that 27 million people exist in slavery around the world today. That number includes more than 60,000 people in the United States alone. Despite the fact that slavery is illegal in every country of the world, it continues to exist in forms such as bonded labor, forced labor and human trafficking. Slavery is the second-largest form of organized crime in the world, generating more than $150 billion annually.

Even more distressing is the fact that nearly 55 percent of forced laborers are women and girls. According to the End It Movement, nearly one out of every five victims of the slave trade is a child, and the average age at which a person enters the sex trade in the United States is 12-14 years old.

The website encourages people from all walks of life to join in by marking a red X on one hand and posting a photo to social media using the hashtag #EndItMovement. You can also donate directly to the organization, or even build your own team to take part in the movement.

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