Nope,??? ?? ?? ??? it's not a giant, red koala, if that's what you're thinking. 

It's actually a Goodfellow's tree kangaroo, an endangered marsupial native to Papua New Guinea. 

This male joey, named Mian, was the size of a jellybean when it was born at Perth Zoo six months ago. Now it's only just starting to poke its head out of its mother's pouch.

The joey is a result of a global breeding program for Goodfellow's tree kangaroos. Perth Zoo hasn't seen one born in 36 years. This time, the pairing of Mian's mother, Kaluli, and father, Huli, which was based on their genetic profiles, seemed to do the trick. 

It didn't start out so well. Kaluli was quite aggressive before she realised what was going on, the zoo's Australian fauna keeper, Kerry Pickles, told The Guardian.

"Eventually, she realised what she was supposed to do and she settled down," Pickles told the publication. "It was his first time trying to breed, so he was a bit patchy at first, but he got the hang of it."

"After the deed was done she got a bit aggressive again, so we separated them," she said. 

Young Mian is one of only 15 males in the program, which will make his genetics "very valuable" when he reaches breeding age, the zoo said in a statement. 

Tree kangaroo joeys stay in their mother's pouches for around six to eight months before testing out their legs.

Mian will stay in the pouch for another one or two months, then he will be sent to another zoo to continue the breeding program, according to the publication. In the meantime, we're loving just how adorable mother and son look together.

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