Joique Bell has gone with his sister, Ambie Bell-Clayton, a few dozen times to her dialysis treatments in the 6½ years since she was diagnosed with kidney failure.

And as hard as it to watch his best friend sit in a sterile room with tubes running to and from her arm, those are some of the best times of Bell’s life.

A few years ago, Bell, a Lions running back, and his sister watched “Remember the Titans” on a screen so small they had to squint. Ambie’s treatment ended before the movie did, and they stayed in their seats because they were so enthralled with the story.

Once, when Ambie wanted a Whopper Jr., she sent her brother on a Burger King run only to have him return with a grilled chicken salad.

“I’m like, ‘What is this?’ ” Ambie said. “He brings me the driest salad Burger King makes. Like, he doesn’t even get dressing. It’s ridiculous, but that’s my brother.”

Mostly, Bell and sister laugh together and joke like they’re kids again, and he comforts her when the machine that cleans her blood and keeps her alive leaves her nauseous once more.

“I admire her,” Bell said. “Like, that’s my hero. She’s the reason I say I can do all this. If she’s doing all that, me coming out to practice every day and watching film and all my hours in the facility, I can really sit down and say if she can go through that, then this is nothing. I’m doing what I love to do. I’m fighting for a job, but my sister’s fighting for her life.”

Today, Bell will take part in the National Kidney Foundation of Michigan’s annual Kidney Walk at the Detroit Zoo in an effort to raise money and awareness for a disease that has afflicted nearly 1 million people statewide.

Next Saturday, when Bell hosts his annual youth football and cheerleading clinic and celebrity basketball game in his native Benton Harbor, the proceeds will go to the Boys and Girls Club of Benton Harbor and the National Kidney Foundation of Michigan.

Though Bell, 26, decided last fall during his first full season with the Lions that he wanted to use his platform as an NFL player to help a cause so close to his family, he kept the news a secret from Ambie, 29, until the end of April when details of his camp posted on the Internet.