A baby who may be the smallest infant ever to survive has been discharged from a hospital more than four months after she entered the world weighing about as much as a cell phone.

Loyola University Medical Center said Rumaisa Rahman was discharged on Tuesday weighing 5 pounds, 8 ounces (2,520 grams), a far cry from her 8.6-ounce (260-gram) weight at birth on September 19, 2004.

The hospital said she is “the smallest surviving baby in the world known in medical literature.” She joins her fraternal twin sister Hiba who was also born on the same day in a Caesarean procedure and who weighed 1 pound, 4 ounces (566 grams) at birth. She was discharged a month ago and now weighs 8 pounds, 8 ounces (3,700 grams).

Doctors said her prognosis was very good and expected that she would have normal physical and mental development.

The babies were born to an Illinois couple originally from Hyderabad, India. They are the couple’s first children, the hospital said. Rumaisa means “white as milk” in their native tongue while Hiba means “gift from God.”