Devon Still’s daughter Leah has been battling Stage IV neuroblastoma since 2014 and was told by doctors that she only had a 50-50 chance to live. Yet in an inspirational turn of events, five years later, not only is she a cancer survivor, her father has also retired from the NFL to tackle a new passion: supporting other families dealing with childhood cancer.

Since 2017, the dynamic father and daughter duo have used their public platform to help raise more than $1 million for cancer research, and Leah has not only won an ESPY Award for her courage, but also appeared in the “Truly Brave” video starring Cyndi Lauper and Sara Bareilles.

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Still, 29, who is promoting his new book, “Still in the Game,” spoke to the TODAY show about all the things he wished he had known prior to becoming a cancer dad.

“I wish I would’ve known that I needed to take better care of myself because it would’ve allowed me to take better care of Leah,” explains the former Cincinnati Bengals defensive tackle. “You can’t give what you don’t have. Most parents forget to take care of themselves because they’re too busy focused on taking care of their child. We think we are helping but we are truly hurting them and ourselves without knowing.”

“I wish I would’ve know it was OK to be vulnerable in front of Leah because we wouldn’t have bottled up our emotions to help each other stay ‘strong’,” he continues.

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“I wish I would’ve known that it truly wasn’t my fault for what Leah was going through. When you find out your child has cancer you immediately start beating yourself up about what you did wrong, what you could’ve done different (foods, drinks, etc.), why you didn’t notice the signs sooner.”

The most valuable advice Still has for other parents of children with cancer is to always keep hope alive, even when things seem dire and the odds feel slim.

“No matter what the doctors were saying, no matter what I read on the internet, no matter how stressed I was, no matter how much pain we were in, no matter how many treatments failed, no matter how many times I felt like giving up, as long as Leah was alive, we still had a chance, we were Still In The Game!” he concludes.

“Still in the Game,” by Devon Still, is available on Amazon.