The child was transferred from the island of Leros to Crete on Saturday, where it died on Tuesday.
A coroner said on Wednesday that the baby died from multiple organ failure brought on by malnutrition.
Relatives of the 24-year-old mother claimed that she had been instructed to feed the baby every three hours with formula and chamomile tea alternately. This led to the baby not receiving the nutrients it needed, the family said. They insisted that there was no evidence that the child had been mistreated.