A tiny chihuahua puppy and a giant great Dane have formed an unlikely bond after meeting at an animal rescue.
The cute friendship began when Shirley Zindler, the founder of Dogwood Animal Rescue in Sebastopol, California, took in five inch-long, 2lbs Bianca six weeks ago after the newborn pup's mum died in labor.
Gentle giant Shelby, a blind three-year-old, 8st 5lbs Great Dane, had already been adopted by Shirley in May 2017, and when the animal lover had to bottle feed Bianca from birth in November, Shelby would sit and watch.
As Bianca grew, the pawsome pair began engaging with each other more and more - most of the time playing around in Bianca's play pen - and Shirley's adorable videos of them playing together online have since gone viral.
Mum-of-two Shirley, 51, a retired animal control officer who now runs the rescue full time, said: 'Bianca is five and a half weeks old and we took her in after her mum died in labour and the owner reached out to us for help.
'She was first introduced to Shelby when I started bottle feeding her from birth, and Shelby would just sit and watch us both.
'When Bianca started to grow, she began playing and engaging with Shelby more and it was so endearing.
'Shelby is very sweet and gentle but also has a wild and playful side to her, whereas Bianca is a little terror!
'Shelby is quite patient with Bianca but will push her away to make her stop if she's biting.
'They clash in size and personality but they have become friends - at the rescue we have a saying that goes 'big or small, we love them all'!
'Their friendship is so unique and it's unusual to see different sized dogs that manage to play with each other.'
Shirley looks after 12 adult pooches at her home - five which are pets of her own, four visiting dogs from the rescue project and three more permanent rescue dogs which she is fostering.
She also cares for 10 to 20 pups and other animals, such as cats.
'She was first introduced to Shelby when I started bottle feeding her from birth, and Shelby would just sit and watch us both. When Bianca started to grow, she began playing and engaging with Shelby more and it was so endearing,' said Shirley
She adopted Shelby two years ago when she was surrendered to the shelter by her previous owners, as she was blind due to an eye defect, and had to go through four gruelling surgeries and have six lots of eye drops every day.
The pooch was nursed back to good health and has now taken on the new role of looking out for the tiny but feisty Bianca.
Shirley said: 'It's very important for puppies to grow up with a mum and to be around other dogs, but Bianca doesn't have a mum and I think Shelby naturally warmed to her.
'We've raising another litter of five puppies that were found in a bag on a porch, and we have a house full of generous aunties waiting to look after them.
'Bianca has already got a home waiting, so unfortunately the two friends will soon part ways and Shelby will move onto the next puppy.
'I think they'll both do fine - it's like kids at camp who spend all summer together but go their separate ways once it's all over.'
Despite the news Bianca will soon be leaving in two weeks' time, she and Shelby have been such a hit online, that commenters have even suggested the animal rescue should create a calendar of the pair's adorable photos together.
Shirley added: 'People love a good story about animals getting saved because it's encouraging instead of hearing about hard times.
'I love it, it's always an extra bonus when you see a sweet bond between the dogs and I'm always fascinated at who becomes friends with who - they're like people!'