The MTV star said that he bought the running shoes to "inspire me to get out and work through the pain" of his daughter Azaylia's death

Ashley Cain is donning new footwear in honor of his 8-month-old daughter Azaylia Diamond, who died last week after a battle with leukemia.

On Sunday, The Challenge star, 30, shared a heartfelt message on Instagram alongside snapshots of new orange running shoes that he bought as a tribute to his baby girl. The color orange is associated with leukemia awareness.

"Right now, It's taking everything I have to begin each new day," said Cain. "The pain of not being able to see my little girl is consuming my whole body. So this afternoon, I put on my new running trainers that I bought after Azaylia gained her angle wings. I got them in orange to represent Azaylia and her battle, in the hope they would inspire me to get out and work through the pain."

He continued, "For days I've wondered when I would have the strength to put them on and hit the road. The truth is, I don't feel strong, I feel far from it. But in times of weakness, I have come to think... 'What would Azaylia do?' She would be strong, she would be courageous and she would get up, get out, and do what is needed to be done. She would push through every challenge with intent and without hesitation."

"So that's exactly what I'm going to do!" the reality star added. "I guess the pain will never fade and things will not get easier, but we will get stronger. 🧡 #LetsGoChamp#AzayliaDiamondCain."

Last weekend, Cain revealed the tragic news of his daughter's death. Since then, he has been open on social media about his grief.

In a message shared on his Instagram Story Saturday, Cain thanked his followers for their love and support, and said that he is "broken and hurting more and more everyday right now."

The MTV star added that he "made a promise to my daughter that I would keep her name alive by continuing to help other children, adults and their families during their own battles and I will honor that promise until I see her again."

Ashley Cain daughter Azaylia
Ashley Cain and daughter Azaylia
| Credit: Ashley Cain/Instagram

Girlfriend Safiyya Vorajee also honored the pair's daughter on her Instagram Story Saturday, sharing a photograph of Azaylia and writing, "so beautiful I think about you all day and night."

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Ashley Cain
Ashley Cain and Safiyya Vorajee with their daughter Azaylia Diamond
| Credit: Safiyya Vorajee/instagram

RELATED VIDEO: The Challenge's Ashley Cain Says Baby Daughter Has 'Days to Live' After Discovery of Cancerous Tumors

Cain first shared news of Azaylia's leukemia diagnosis in October, revealing that his then-2-month-old baby girl had "a very rare and aggressive form" of cancer.

In February, Cain said the family was "urgently informed that Azaylia's leukemia had returned" moments before she was due to leave the hospital after a stem-cell transplantation.

Shortly before her Azaylia's death, Cain was told to "make the most" of his time with his daughter by doctors who told him that the infant was nearing her final days.