Last week the San Francisco Zoo welcomed a rare occurrence — the live birth of twin reticulated giraffes in captivity — which turned into a bittersweet event after one of the two twins died two days later. But the stronger of the two calves was born very healthy, weighing 100 pounds and standing 5-foot-6-inches tall, and immediately started nursing. This is only the tenth ever recorded birth of twin giraffes in zoos worldwide.

The mother of the calf is 11-year-old Bititi, born at the Oakland Zoo, who has now given birth four times. The latest birth happened on Tuesday, August 26, at 8:30 a.m., and Bititi and the unnamed calf were both out feeding in the south corral of Osher Family Giraffe Lodge on Friday.

Sadly, the second calf was born very weak and unable to nurse on its own, and post-birth complications led to its death on Thursday.

Zoo President Tanya Peterson said, "This is a bitter-sweet announcement to make, but this very unique twin birth is something for all of the Bay Area to take pride in." She added that she hopes locals will come and "give a warm welcome to our newest resident."

Though reticulated giraffes are not endangered, populations have been decimated in western and southern Africa, and are primarily found in lightly wooded savannas of northern Kenya and Ethiopia. Baby giraffes are born, usually singly, while the mother is still standing, after a 422- to 450-day gestation period. They can grow to be 18 feet tall and weight 3,000 pounds.

Watch for more announcements about the new baby on Facebook.