Bengals DT Devon Still explains how he has been able to cope with his 4-year-old daughter Leah's Stage 4 cancer diagnosis with the help of the Bengals organization and support from fans and even Saints coach Sean Payton. (6:32)

Thursday will be one of the longest days of Devon Still's life.

There's a high likelihood he may shed a few tears.

But early in the morning, before driving his 4-year-old daughter, Leah, to the Children's Hospital of Philadelphia, he couldn't let her see how scared or nervous he really was. He needed to be strong so that she could be strong.

In a video Still posted to his Instagram account Thursday morning, the Cincinnati Bengals defensive tackle gives a pre-surgery pep talk to Leah from inside the car. As he sits in the front seat with the camera pointed toward him and the smiling little girl in the back seat known by friends and family as the "selfie queen," Still has one question.

"I'm going to ask you again," Still asks Leah. "Are you ready for today? I'm ready for today."

As she continues to smile from the back seat, Leah slowly nods.

"You ready to get this cancer up out you?" Still asks.

She smiles and nods once more.

"Let's do it. Fist bump."

They both give a fist bump toward the camera.

Still, back home this week as the 3-0 Bengals take their bye ahead of a Week 5 contest at New England, has had his mind on his daughter's cancer fight since June 2, when doctors discovered that she had neuroblastoma, a pediatric cancer that has left her with a 50-50 chance of survival. Last week, doctors reassessed the size of the tumor and noticed that it had gone down ahead of the surgery that was scheduled for Thursday.

Doctors are hoping to remove the tumor before placing Leah back under another round of chemotherapy, radiation and stem-cell transplants in an effort of regenerating her bone marrow and stem cells.

A few of Still's teammates offered their support on Twitter:

Prayers for Leah Still this morning !!! - Darqueze Dennard (@DDennard21) September 25, 2014

With Leah's battle weighing on him, Still acknowledged earlier this month that his mind wasn't 100 percent on football during the preseason and training camp. A hamstring injury also sidelined him near the end of the preseason, forcing the Bengals to cut him when they needed to reach their 53-man roster limit. A day later, the former second-round draft pick was added to the practice squad, allowing him to retain his NFL medical insurance and a spot in the league.

Still's mission this past month has been to raise funds for pediatric cancer research. The Bengals assisted with those efforts two weeks ago when they started selling his jersey out of their pro shop. All proceeds are going to Cincinnati Children's Hospital. After four days, they raised about $400,000, including a sizable amount from New Orleans Saints coach Sean Payton, who purchased 100 jerseys to give to children in the Cincinnati area. Other fundraising efforts are sending money to the Children's Hospital of Philadelphia.

Granted permission to leave Cincinnati a day early, Still arrived in Wilmington, Delaware, on Tuesday to help set up a pre-surgery party for Leah that was held at a movie theater Still rented out Wednesday.