This Sunday, Jews around the world will commemorate Kristallnacht, also called “Night of Broken Glass,” one of the most brutal single events of the Holocaust.

Seventy years ago on Nov. 9, 1938, violence against Jews broke out throughout Germany. Over two days, angry mobs burned, looted and destroyed synagogues, homes and Jewish businesses. (The word Kristallnacht refers to the shattered glass from the store windows that littered the streets.) About 100 Jews died during these pogroms.

Some older Jews living in the United States are still reliving days like these. About 93,000 Holocaust survivors are alive in the U.S., according to a report in The Washington Post on Sept. 14. South Florida has one of the largest populations.

While they have lived full lives, their memories are still intact and can play tricks on them. Flashbacks can come at any time and can be triggered by a certain sound or smell that may remind them of the horror they experienced or witnessed, according to the news article. One survivor mentioned in the story began screaming on a High Holy Day because musicians were playing music that was played as murders took place at concentration camps.

Flashbacks are expected to worsen as these seniors age, especially if they have dementia.

Some Jewish organizations worldwide actually work to keep survivors at home, providing nurse aides and delivered meals—and away from nursing homes where uniformed nurses, shower rooms and even medical procedures may set off nightmarish memories.

Let’s take care to remember this group of elderly always, but especially this Sunday.