GiGi's Playhouse ready to celebrate its first World Down Syndrome Day World Down Syndrome Day is 3/21 GiGi's Playhouse was supposed to open last year on World Down Syndrome Day, but the opening was delayed until August due to COVID-19. and last updated 2021-03-16 23:52:41-04 BUFFALO, N.Y. (WKBW) â GiGi's Playhouse Down Syndrome Achievement Center of Buffalo is getting ready to celebrate its first World Down Syndrome Day. The celebration comes exactly one year after COVID-19 delayed its March 21st opening to August. "So Down syndrome occurs when there are three copies of the 21st chromosome," said Board President Will Mondschein. "So every year on March 21st, or 3/21, the world gets together and celebrates individuals with Down syndrome and really tries to also raise awareness for people that may not know much about it."