After losing her litter of puppies at birth, Molly the beagle was having a ‘ruff’ time.

That was, until a paw-some new friend came into her life, just days later.

A baby possum jumped on the dog’s back, and has made herself comfortable in the saddle.

Molly and Poss, the best of buds. (9news)

“They've been inseparable ever since,” Molly’s owners, Elle and Sara Moyle, told 9News in south-west Victoria.

The bushy buddies might be from different parts of the animal kingdom, but they share a special bond.

Molly- a mother without her pups- and Poss (what the Moyle’s have affectionately named the new arrival)- abandoned by her mum.

“They're an unlikely pair, and I think that possum thought Mol was her mother and vice versa,” Ms Moyle said.

Navigating the Moyle's Gazette cattle property is quite the challenge for a baby possum.

So she hitches a ride on her bestie’s back. Far from weighing her down, Molly is happier than ever with her mate.

“It's certainly uplifted her mood, they both needed each other I think so it's been a fantastic relationship,” Sara said.

Nine News met the inseparable pair at their home in Victoria. (9news)

Being nocturnal, Poss spends her days sleeping in the trees around the property.

Rather than forget about her when the sun is up, Molly's owners said she's still keeps an eye on her.

“Molly just sits under the tree where she's sleeping and just waits for her,” Elle said.