No one expected this tiny kitten with a broken heart to live to see her first birthday, but the kitty kept beating the odds.

Thumbelina and her three brothers came to Rescue Me Animal Sanctuary from an accidental litter. "She was less than half the size of her brothers so straight away we knew she was special," the rescue told Love Meow.

They gave her a health check and were hoping that with some TLC and one-to-one care that she would start to catch up. Over the next 48 hours, they noticed that she would tire easily, and after a little play session, she collapsed and became very pale. They took her back to the vets.

Thumbelina was born with a heart defect but the little tuxedo wouldn't let anything stop her.

Thumbelina desperately needed an ultrasound with a specialist vet to help them decide what the best treatment was for her, but they had to wait for another month as the kitten was too small to scan at the time.

Her feline siblings went off to their forever homes while they continued monitoring Thumbelina in her foster home.

Once she had her scan, the results revealed a very poor prognosis.

She had severe problems with the valves in her heart, and there was no surgical treatment available and she was not expected to live to see her first birthday.

"She had a heart scan and sadly had several defects and a valve which hadn't grown correctly. The specialist said she had done amazingly to survive this long but it was highly likely that she wouldn't make the first year," the rescue told Love Meow.

Despite it all, Thumbelina was always in good spirits and wanted nothing more than to be with her foster parents.

"There is no operation or medication that can help the kitty due to the complexity of her issues," the rescue added.

"So her loving foster parents (Colin and Anna) decided that they would keep Thumbelina for however long she had."

"She was thriving as any normal kitten but just at a slower rate and also half her size for her age. She did tire easily after a play but took herself for a rest."

Colin and Anna never gave up on their little bundle of joy and showered her with love and cuddles every day.

Fast forward to today, Thumbelina reached another major milestone and stunned her vets with her amazing will to live.

"The heart specialist said she probably wouldn't see her first birthday but here we are. She has turned one today!"

The tiny kitten who was half her size for her age, has blossomed into a gorgeous tuxedo cat.

She may have a broken heart but she has so much to give.

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