During World War I, families began to fly service flags. Each blue star on the flag represented a family member that was serving, and each gold star represented a service member who had fallen. “This allowed members of the community to know the price that the family had paid in the cause of freedom,” the Army website explains. These Gold Star families are now represented and supported in several ways, including Gold Star Mothers Day, which was observed yesterday.

On social media, tribute was paid to these mothers:

Today is Gold Star Mothers & Families Day. Remember the Fallen, and their Families. https://t.co/8GAbwQNgek #GoldStarMothersDay

— Whisky and Tartan (@whiskyandtartan) September 28, 2015

To the Gold Star Mother: Our country owes you so much we can never repay. But we are grateful: #GoldStarMothersDay pic.twitter.com/qf8JqW0obM

— Randy Forbes (@RepRandyForbes) September 28, 2015

Loss of not 1 but TWO sons, God Bless the Wise family #GoldStarMothersDay RIP Jeremy KIA 12/30/09 Ben KIA 1/15/12 pic.twitter.com/BAUIiNHhPV

— JoJo (@JoJoLongIsland) September 28, 2015

Honoring our Gold Star Mothers and their families, we will never forget your loved ones #GoldStarMothersDay pic.twitter.com/EvooVpuLS1

— VN Vets Memorial (@VVMF) September 27, 2015

Behind every Gold Star Pin is a story of loss and strength. #GoldStarMothersDay #GoldStarFamily https://t.co/CvbqDzRvZr

— U.S. Dept of Defense (@DeptofDefense) September 27, 2015

Blessed are those that mourn, for they shall be comforted. – Matthew 5:4 #GoldStarMothersDay pic.twitter.com/WcP0hQLH31

— Janine Stange (@THEANTHEMGIRL) September 27, 2015

Sharing love, respect and support for our nation's Gold Star Mothers. #GoldStarMothersDay pic.twitter.com/JeSC2rzsoR

— Semper Fi Fund (@SemperFiFund) September 27, 2015

Today—& every day—we honor the sacrifices of women like my mother-in-law. God bless them all. #GoldStarMothersDay 🌟🇺🇸 pic.twitter.com/T2zjYIOpS9

— Judge Don Willett (@JusticeWillett) September 27, 2015