Blue Star families are defined as those families having a member currently serving on active duty during wartime. It was designed and patented during World War I, by an Army captain in Ohio whose two sons were serving on the front lines. The banner became a symbol that families would proudly display to let their neighbors and townspeople know they had one or more family members serving.
World War II saw this practice resumed and became very popular. Banners were standardized and guidelines created as to the size of the banner as well as who was eligible to display it. Lapel pins also came into fashion, with the same restrictions as to those who could wear them.