In July 2018, my family planned one of the biggest family reunions in years which included everyone in every branch from my dad's side of the family - and he has four sisters. To keep organized and to avoid the awkwardness of not remembering someone's name of whom you met when you were 10 years younger, my aunt commissioned me to design these buttons which she would cut out and physically press into pins.
Each branch of the family had its own color, I've shown all 5 below.