PITTSBURGH (KDKA) — Pittsburgh Zoo & PPG Aquarium has gotten the most adorable gift this Christmas season.

Twin clouded leopard cubs, both boys, were born at the zoo back on Nov. 27.

(Source: Pittsburgh Zoo & PPG Aquarium)

This is the second litter for parents, Saya and Pi.

Unfortunately, the zoo says after several unsuccessful tries to get them to nurse, Saya gave up, and did not return to them.

Karen Vacco, the zoo’s assistant curator of mammals, said in a press release: “We are disappointed. It’s definitely not the outcome we had been hoping for. Saya showed maternal instincts when she cleaned her cubs and positioned them to nurse several times, but after the cubs failed to latch on, Saya left them.”

That’s when zookeepers decided to intervene and removed the cubs from the nesting box for their own safety.

The zoo’s Director of Animal Care Dr. Ginger Sturgeon said: “The two cubs are healthy and doing well. They feed every four hours and are gaining weight. Their eyes are slowly starting to open and they are starting to become a little more curious of their surroundings. They haven’t fully developed their coordination yet so they try to pull themselves up to crawl but they can’t quite get the motion down yet.”

The cubs will be cared for in the zoo’s Animal Care Center for several more weeks.

Saya is also the mother of Rukai. She was born at the zoo in April, and most recently got a new male companion, JD, back in October.

Stay with KDKA for the latest on this developing story.