Ten-year-old Nababiep, an African lion at the National Zoo, gave birth to two live cubs on Friday. (Smithsonian National Zoo)

The National Zoo announced Monday that one of its African lions delivered two live cubs Friday and one that was stillborn.

Ten-year-old Nababiep gave birth to three cubs in an eight-hour period. The cubs are the third litter for Nababiep, and the fourth for the 8-year-old father, Luke.

Two female lions, Shera and Nababiep, and the male, Luke, live at the zoo’s Great Cats exhibit. The zoo said Shera may also be pregnant.

The first cub was born at 3:58 a.m. and appeared active and healthy. Five hours later at 8:51 a.m., Nababiep delivered the stillborn cub. The third was born at 11:24 a.m. and was also healthy.

It is not uncommon for lions to have some healthy and one or more stillborn cubs in the same litter, the zoo said.

Nababiep, left, is seen in 2011 with an earlier cub, Aslan, and a cub from another mother, Zuri, right, at National Zoo. (Matt McClain/The Washington Post)

“The first few days of a lion cub’s life are very fragile,” said Rebecca Stites, an animal keeper at the Great Cats exhibit, according to a zoo statement. Nababiep’s first cub, born in May 2010, only lived 48 hours. A piece of bedding straw had become lodged in one of its lungs, which resulted in pneumonia. The zoo said the mortality rate for lion cubs in captivity is about 30 percent, compared to 67 percent in the wild.

This litter will not be on exhibit until late spring, the zoo said.