KANSAS CITY, Mo. — Before Mike Pennel left the house, his mother would spread a Lidocaine ointment onto his chest, numbing the skin so that when doctors stuck a port in her baby boy, he wouldn't cry.

The chemotherapy program stretched a year and a half. Eighteen months of driving back and forth from Topeka to Children's Mercy Hospital in downtown Kansas City, where nurses would hook Pennel up to an IV for four-hour sessions, and he'd flip on the TV and watch a purple dinosaur sing.

On Monday, some 25 years later, Pennel strolled through those same hospital doors, this time a visitor rather than a patient. Now a hulking Chiefs defensive lineman, he returned to the place forever etched into his memory. To the setting of the first thing he thinks about each and every morning.

"This looks familiar," he would say after scanning the lobby.

He arrived gripping a sack of toys in one hand and a bag of them strapped over the opposite shoulder. Video game controllers in the plastic sack. Board games in the enlarged gym bag.

He took the elevator to the second floor. Kids receiving dialysis treatments were waiting for him. Moments before he entered their room, he stopped briefly, outlined a religious cross on his chest where the port once entered and pointed upward.

He handed out the games to T, Avery, Hayden and others. T wanted Jenga. Hayden took Uno. Pennel snapped pictures with them. Signed Chiefs hats he had brought. Told them he once sat where they did now.

After half an hour, as Pennel finished speaking with a young patient, he turned around.

"Oh, my God," he said. "Look who it is."

In the hallway stood a longtime longtime doctor at Children's Mercy, Alan Gamis. Pennel pointed him out to his mom, Terri, but quickly realized she had already spotted him, tears streaming down her cheeks.

"That man saved my life," Pennel says. "You know, I'm not supposed to be here right now."

Terri never had the slightest indication something was wrong with her son. The day care required kids to get routine physicals. At the appointment, doctors discovered a knot in Pennel's belly. He was just 2 years old.

The physical was scheduled on a Wednesday. By Friday, he was in surgery to remove two tumors, one attached to each kidney.

He had Wilms' tumor, a rare kidney cancer that affects only 500 children per year.

"Devastating. Gut-wrenching," Terri says. "Even thinking about it now, I still get choked up about it."

An experimental cocktail comprised the chemotherapy. Gamis was more hopeful than certain of its success. And even if it did work, there remained a 10% chance of recurrence.

Pennel entered this world abnormally large — born nine pounds, 11 ounces. "I came out on a protein program," he jokes now. The delivery doctor voiced concern Pennel had broken his shoulder during the birth because he was so big.

When Pennel was a few months old, Terri noticed a development defect. The right side of his body appeared to be growing at a more rapid rate than the left. He had Hemihypertrophy, a genetic disease. They considered shutting down a growth plate to level him out. Years later, as he participated in studies, Pennel learned the two were connected — Hemihypertrophy and Wilms' tumor.

Pennel recalls bits and pieces of the battles he endured, mostly from the subsequent treatments that would span nearly a decade.

As he sat down for lunch Monday inside the Children's Mercy cafeteria, he picked a kids table, one at which he likely used to eat. A 332-pound man — the largest on the Chiefs' roster — squatted on a plastic chair reserved for toddlers.

He shared his story over a hamburger and bowl of soup, his mom filling in the blanks. Their family had not experienced previous tragedy, she says. Pennel was unfamiliar with death.

But he asked. On occasion, as young as 3, he would make comments about the possibility of dying. "If I live that long," he would end sentences or thoughts, saying it matter-of-factly.

He asked his mom about Heaven. He wondered about the possibility of going to sleep and not waking up. She answered honestly.

As the days passed and the treatments progressed, Terri realized her son's personality had endured a change. In a weird way, she explains it, "he was starting to become so at peace with not making it to adulthood."

On Christmas Day in 1996, when Pennel was 5, he had finished opening up all of his gifts when Terri asked if he received everything he wanted from Santa.

Pennel shook his head no.

Terri looked around, her kid sitting on a floor surrounded by toys, miffed by the response.

"What do you mean you didn't get everything?" she said.

"What I really, really, really want," he replied, "is to play in the NFL."

Throughout childhood, Pennel had spoken almost strictly of the short-term. When talking about growing up, he prefaced a thought with acknowledgement he might not live to see those days.

Football was the exception. He always saw the future.

Gamis informed Pennel that if he reached 10, cancer would be part of his past, no longer part of his present. So on his 10th birthday, after the family had moved from Topeka to Denver, Pennel requested a weight set. Terri inquired about the idea with the pediatrician, who advised against lifting. He was too young.

A year later, Pennel requested a physical trainer.

"In my mind, I thought, I'll humor him," Terri says of the NFL goal. "This probably isn't happening. But if this is what makes him happy in this moment, we'll roll with it. Because I wasn't thinking about him being 18 or 20."

Terri took it to the fullest, even serving as an instructional coach, of sorts. Pennel didn't have a relationship with his father, who spent time in prison. They later exchanged letters, but that didn't last long, either.

Terri worked as a nurse, volunteering for double shifts. She's only once missed one of his football games — this year's trip to Mexico City.

"She never played football in her life, but she's teaching me football," Pennel says. "I'm sure she watched videos, because she was teaching me how to run and talking to me about aggressiveness at 9."

The absence of a father triggered a mean streak, Pennel believes now. It benefited him on the football field. Not elsewhere. He acted up at school. Regularly engaged in fist fights. Didn't pay attention to his grades and ignored classwork.

Football provided his only inclination of self-discipline. He checked his weight almost every day, trying to get as big as an NFL lineman. When he stepped on the scale in seventh grade, the reading showed 250 pounds.

He watched the NFL combine from start to finish, taking notes while sitting in front of the TV for eight hours at a time.

"I knew what I wanted to do," Pennel said. "And I knew I was going to make it."

If he had the discipline to get there.

Pennel never graduated high school. Once he discovered his grades made him ineligible to play football, he gave up trying in class altogether. He qualified to play only two of his four high school seasons and later took and passed a General Educational Development (GED) test.

"I told him he better have a Plan B," Terri says. "Because his football dream wasn't going to happen unless his grades came up."

Pennel relented. He agreed to come up with an alternative, just in case. He'd take college more seriously, he told her.

But he bounced around. Started with junior college. Then a scholarship to Arizona State. Then back to Division II football in Colorado.

He didn't get along with coaches at some of those stops. Found others dishonest.

Terri eventually supplied some brutal honestly — in a way only a mother could.

"Mike, this can't always be everyone else. At some point it's gotta be you,'" she said. "God didn't spare you for you to go out and waste this chance."

On a 2014 evening at historic Lambeau Field in Green Bay, Terri sat in the stands alone. She wore her son's jersey — she swore it would be the only football jersey she would ever buy.

Minutes before a game, the Packers came charging onto the field. On the JumboTron, she spotted him.

No. 64.

Mike Pennel.

"I full-blown cried like a baby," she says. "Because only we understood what he'd been through."

Pennel thinks of the journey every day. In the morning as he wakes. In the evening before he falls asleep.

When he lifts his shirt, it reveals a long scar from one hip to the other, where doctors cut into his stomach to remove the tumors. His body is littered with tattoos. On one arm, at 15 years old, he inked a beast emerging from his skin. He's taken on that moniker — the beast. On the other, his mom designed a tattoo that reads, "Watched by angels. Blessed by God. Destined for success."

Pennel has been an unexpected bright spot in Kansas City. He has 18 tackles, one sack and two tackles for loss from an interior line position in seven games as a reserve after the Chiefs picked him up mid-season.

At every stop in his life — childhood, college and the NFL — he's had opportunities to give up the dream. Even after receiving an invitation to the NFL combine in 2014, he went undrafted. Some wondered if that would be it. But he told his mom he needed just one shot to prove his worth.

Green Bay gave him one, an invitation to rookie mini camp and then an extension into training camp. After the first day in pads, he knew he belonged.

When the coaches ultimately informed him he had made the team, he walked to the locker room and called his mother first. She had been working and unable to follow the news that day. To be honest, the cut deadline had completely escaped her mind.

They talked for a bit before Pennel finally relayed the news.

"Just so you know," he said. "There never was a Plan B."