A little boy comforting his sister who was battling cancer is breaking hearts across the internet.

In November 2016, Adalynn Joy Sooter was given only months to live after doctors found a tumor in her brain, People magazine reported. But after fighting the cancer that was attacking her body, she lost her battle after nearly 19 months.

Adalynn, or Addy as her family called her, first posted her story on the "Love What Matters" web page.

In the post, they recounted how they noticed that their 2-year-old had a “hitch” in her step. The “hitch” got worse. She had trouble walking and holding her fork or spoon.

Doctors found a tumor on her brain stem and diagnosed her with diffuse intrinsic pontine glioma, or DIPG, People reported.

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Despite the prognosis that she only had months left, Addy had radiation treatments and the tumor shrank to half its size, but it came back and in July 2017, the family got the devastating news that doctors could do nothing more for Addy,

But there was hope of an experimental treatment in Mexico. But the treatment wasn't as effective as they hoped and they saw Addy's health fail, People reported.

She died from DIPG earlier this month. Her father, Matt, shared the news on Facebook: "She passed from this life to the next just as she had lived: stubbornly but also peacefully, and surrounded by family. She wasn't in any pain in the end."

But it is the photo of Addy with her brother that is showing the heartbreak that families fighting childhood cancer can go through. The image shows Jackson trying to comfort his sister, with his hand on her head. Matt posted that Addy didn't have much time left.

Matt wrote, "A little boy should not have to say goodbye to his partner in crime, his play mate, his best friend his little sister."