That missing sock from the laundry may have finally found its purpose -- as a reminder of the many thousands of missing children.

For National Missing Children’s Day on May 25, John Walsh, the former host of “America’s Most Wanted” and co-founder of the National Center for Missing and Exploited Children, and his son, Callahan Walsh, are launching a new campaign called "Rock One Sock."

The concept behind “Rock One Sock” is that when a sock goes missing in the laundry, there is always hope to find it. Their campaign leverages that same sense of hope for finding missing kids. During the month of May, Walsh and his son are asking everyone to wear one sock, take a “footsie” photo, and then post it to social media using the hashtag #RockOneSock.