Against all odds, an adorable success story is unfolding at Australia's Symbio Wildlife Park, where two young koala joeys are getting a second chance at life.

Imogen and Harry were born at the park earlier this year, but when 22-week-old Harry's mother died of leukaemia, the staff had to get creative to keep both youngsters alive. After consulting with veterinary staff and wildlife experts, a decision was made to hand-rear Imogen, who was the oldest and strongest of the two. In doing so, the team would be able to use her mother, Kelly, as a surrogate for Harry.

The process has been challenging, but the hard work is paying off – and Imogen has also happily settled into her role as chief supplier of the world's baby koala cuteness. To mark her first year, Symbio released a peek at a celebratory photoshoot.

To help their bodies make the transition from milk to leafy greens, koala babies must eat "pap", or digested eucalyptus leaves. The pap – which, yes, must be excreted by mom koala first – helps trigger the production of important enzymes in the young kolas' digestive systems. Because Harry's mother died when he was just 22 weeks old, he hadn't yet received this critical nutrient. Imogen, on the other hand, had already started to emerge from her mother’s pouch and was getting the hang of eating eucalyptus on her own. (As you can see in the video, she's now a total pro.)

But don't let all that cuteness fool you – the job of stand-in koala parent is way tougher than it looks. "Hand-raising Imogen has been the most challenging and rewarding thing we have ever achieved,’’ staffer Kylie Elliott told The Mercury. "It hasn’t been an easy journey raising a joey with nocturnal habits and sharp claws. I definitely have a new respect for koala mothers."

Thanks to the team's dedication, Harry has also been doing well. After successfully taking to surrogate mother Kelly, he's now grown from 250 grams to a healthy 900.