"Hannah, if you're reading this then the surgery did not go well."
This is the opening line of the worst letter Hannah could have ever received - and one that is breaking the heart of internet users all over the world.
Hannah Summers, 18, shared the final letter her mother wrote to her before dying of cancer.
The letter includes the final words of advice from her loving mother.
"Please don't be mad, bad things happen in life and we have to learn to deal with it no matter how much it hurts," her mum wrote.