NFL Player Devon Still And His 5-Year-Old Daughter Documented Their Journey Following Her Cancer Diagnosis. And It's Touching.

'I am Leah Strong.'

Leah Still is only 5 years old, yet her bravery and strength has won the hearts of many. 

Leah is the daughter of Devon Still, defensive tackle for the Cincinnati Bengals. Last year on June 2, 2014, Still received devastating news about his daughter's health. 

Leah was diagnosed with Stage 4 neuroblastoma. The American Cancer Society states that neuroblastoma is a type of cancer that starts in early nerve cells and occurs most often in infants and young children.

"Our whole world just flipped upside down," Still shared on a video posted on a site for Leah. "I don't want to lose my daughter. And it scares me to death that she has a chance of not being here. She's my best friend, I love that girl to death. I don't know how I would be able to hold myself together if something ever happened to her."

Still's pain can be seen, heard, felt and certainly understood as the professional athlete has documented his family's journey following Leah's diagnosis, showing moments of courage, strength, optimism and even happiness.

Being the fighter that she is, Leah used her personal experience as an opportunity to help others going through similar journeys.

Leah and her dad wrote "I Am Leah Strong," aimed to help other children battling cancer. According to Still's caption, a portion of the book's proceeds will go towards efforts focused on pediatric cancer.

Leah and Still's documented journey captivated people all over. 

Along with an outpouring of likes, uplifting messages and shares on Still's social media, he and Leah will also be recognized at The ESPYS award show. 

According to ESPN, Still and Leah will receive the Jimmy V Perseverance Award in light of the way they handled Leah's battle with cancer. The pair will be honored at The ESPYS award show on July 15 in Los Angeles. 

"The perseverance that Devon and Leah have shown throughout this unfortunate process is incredibly moving," said Connor Schell, the senior vice president of ESPN Films and Original Content and overseer of The ESPYS, ESPN reported. "Each day that she fights, her father is by her side, and their love and strength has captivated all of us in the sports world and beyond."

Still has allowed people to join him in this difficult journey. Through the highs and lows, his supporters took the ride along with him and Leah. On an exceptionally high moment on March 25, Still shared that Leah's doctors declared her cancer was officially in remission. Many shared in his joy and excitement on Instagram.

Months following this happy news, Still recently shared unfortunate news that Leah endured a complication from her stem cell transplant. He asked their supporters for prayers while promising he will do his best to remain positive.

With all that Leah has gone through this past week, she made a point to give a thumbs up to her supporters. Still's caption reads:

"Can't really talk or smile but she wanted to give y'all a thumbs up to say she is doing better and thanks for the prayers...first time she's really been awake in 4 days so we are making a little progress."

Still shared on Instagram that it was "not a good day" on June 2 and continued to ask for prayers. 

Whether it's difficult to imagine what Leah and her family are going through — or it hits home with a personal experience — Still and Leah's documented journey has touched so many people.

Leah's book, smile and contagious spirit gives us clear understanding to what it means to be #Leahstrong.

Cover photo courtesy of: Devon Still's Instagram @man_of_still75