The Smithsonian’s National Zoo has announced the birth of two bear cubs, who arrived between midnight and 2 o’clock Thursday morning. The cubs are Andean bears, born to six-year-old Billie Jean. Andeans are one of the most endangered bear species in the world. “The Andean bear population in human care has experienced a lull in the past six years, and these cubs are the only surviving Andean cubs in a North American Zoo since Billie Jean’s first cubs, Bernardo and Chaska, were born in 2010,” said a statement from the zoo that announced the births. “This species has a high mortality rate, with first-year mortality at 41 percent for males and 44 percent for females.”

The cubs’ father, Nikki, was “humanely euthanized” in August due to declining health after a cancer diagnosis. Nikki was 20, an almost full life span for an Andean bear in human care.

While the new arrivals are not yet on public view—that may not happen until spring, if all goes well—they can be viewed on the zoo’s “Andean Bear Cam.” The zoo staff are monitoring the family, but say its main objective right now is to “leave Billie Jean to bond with and care for her cubs without interference.”