A little over a month after two-year-old Moshe Holtzberg was orphaned by the Mumbai terror attacks, anguish returned to the households of his grandparents, the Rosenbergs in Afula, Israel, and the Holtzbergs in New York, as his older brother died after over three years in palliative care in Jerusalem.

Dov, Gavriel and Rivka Holtzberg’s second son, was suffering from aged Tay-Sachs disease, a terminal condition that’s among the most common genetic disorders in Jewish babies. He was four and a half years old.

While Moshe — and the baby his mother was carrying when she was killed by terrorists — is free from the genetic condition, his oldest brother, Mendy, also succumbed to Tay-Sachs a couple of years ago.

“He died this morning about 5 am,” said Elazar Gelbahtein, a close family friend of the Rosenbergs, Rivka’s parents.

As Jewish tradition prevents grandparents from “sitting shiva” or accepting condolences for a death, and since Moshe is still too young, there will be nobody mourning the death of Dov, said Gelbahtein.

Dov was in the same facility where Mendy died a couple of years ago. Tay-Sachs is a degenerative and debilitating disease, with patients losing all motor skills, hearing and sight by the time they attain the age of five or six.

When his father was last in Israel several months ago, Dov’s condition was already worsening. Nevertheless, Gavriel and Rivka decided to continue their mission in Mumbai. Members of the Chabad movement said the funeral was attended by both sets of grandparents. “Dov was buried next to his parents in Jerusalem,” said Gelbahtein. “This is a tragedy for everybody in the world who wants peace and love and friendship.” Moshe did not attend the funeral. “He is too small,” said Gelbahtein.