The blood is even harder to find because the donors must have blood types "O" or "A" and be 100 percent of Indian, Iranian or Pakistani descent, Forbes said.
Less than four percent of the world's population has the blood type Zainab needs to undergo treatment, which includes frequent blood transfusions, Forbes said. None of Zainab's family have turned out to be matches, Mughal said.
So far, OneBlood has located three matches, including one in the United Kingdom near London, with the help of the American Rare Donor Program, Forbes said. All three have since sent units of blood to the Miami area, where the family lives, Forbes said.
Zainab will need up to seven more people to donate throughout the course of her treatment, according to the organization. And more than 1,000 people who are of Iranian, Indian or Pakistani descent have donated blood to be tested, Forbes said.