When Nick, 28, leaves for work and returns home, his brother Gabe, 21, who has Down syndrome, gives him a big hug and a kiss on the nose. Sometimes Nick picks up Gabe and holds him in his arms ...

However, Millie, who has Down syndrome, didn't want her big sister's help and expressed her frustration by grabbing Georgi's face. Geib didn't need to intervene, as her five-year-old responded calmly ...

For the past decade, Hilary Gauld has photographed people with Down syndrome, highlighting their stories about navigating love, aging and achieving their goals Anna Lazarus Caplan is a writer ...

A century after Down syndrome was first described, scientists discovered that the root cause of this disorder is a condition called trisomy 21. What strides in research have been made since then?