Damian Lillard speaks to Dr. Martin Luther King Jr.'s courage to stand up for his beliefs and sacrifice his life. (0:30)

LOS ANGELES -- SIX-AND-A-HALF-YEAR-OLD Glenn Rivers sensed something was amiss the moment he skipped into his grandmother's house.

It was suppertime, and his father, Grady Rivers, a longtime Chicago police officer, was there. The father, who was scheduled to be on duty, who patrolled the night shift, never missed a day of work. Yet there he was, slumped in a chair in full uniform, huddled around the small black-and-white television set with Glenn's aunts and uncles.

As Rivers inched closer, he saw his father was sobbing.

"I had never seen my dad cry before," Rivers says. "My grandfather, who was tougher than my dad, was crying too."

The bewildered first-grader tried to piece together what had left his family so broken. Someone, he was told, had been killed. Panicked, he began counting heads in his grandmother's den. Was it a member of the family? A friend up the street?

Grady took his young son by the hand and drove him home in his patrol car.

"And that's when he told me all about this Dr. King guy they were all talking about," Rivers says. "It was the first time I had ever heard of Martin Luther King."

On that day, April 4, 1968, Grady Rivers tried to articulate to his son what Martin Luther King had done to advance civil rights, to fight for racial equality, to use words, not violence, to bring about change.

And now he was dead in a hotel in Memphis, Tennessee, at the age of 39.

From that day forward, Dr. King became a Rivers family companion, his words echoing the teachable moments Glenn's father imparted to him. Grady Rivers played King's speeches on the family record player over and over again, his booming voice literally weaving itself into the family narrative.

"Naturally, as a young kid you are curious," Rivers says. "Dr. King became an extremely important part of my life. He became our Gandhi, in many ways."

Martin Luther King Jr. (seen from behind) and the values he stood for has become an inspiration for many, including Doc Rivers. Stephen Somerstein/Getty Images

Grady Rivers was a fixture in his sons' lives, driving his cruiser onto the diamond and shining the headlights so the boys could play baseball at night. Their Maywood neighborhood, on Chicago's west side, was pocked with violence, poverty and despair, and so many of Glenn's friends grew up without a father, but they found a surrogate in the kind yet firm cop who told his own two boys they'd have to share him.

There were two things Grady never talked about -- his service in the Korean War and what he saw on the streets of Chicago.

"It was a vicious time," Rivers recalls. "So much racial tension ... but we didn't hear one word about it."

When Rivers went to Proviso East High School and made the basketball team, his father sat in the front row of the bleachers, his badge gleaming, to remind his son what was expected of him.

"My brother and I loved going to headquarters and seeing the holding cells," Rivers says. "Sometimes, you'd see people you knew in there.

"My dad always told me, 'Let me tell you something, son. If you are on the other side of those bars, I'm not doing anything to get you out.'"

GLENN RIVERS GREW up to be a star basketball player at Marquette. He dated a pretty blonde named Kris Campion and fell in love. It didn't occur to him that anyone would object so strongly to a mixed-race couple until they slashed the tires of Kris' car and spray-painted her parents' home with racial epithets. The cowardly crank calls meant to unnerve them inflicted more bruises.

Grady counseled his son to resist his anger and his hurt and harken back to Dr. King's philosophy.

"People have somehow decided love is a soft word," Rivers says. "Love is a tough word. As Dr. King often said, 'The more they hate you, you must love them more.'"

Rivers married Kris in 1986 and joined the NBA fraternity as a gregarious point guard known simply as "Doc." They had four children. The third one, Austin, plays for his father on the Los Angeles Clippers.

Rivers dealt with challenges on and off the court while he was a star player at Marquette. Marquette/Collegiate Images/Getty Images

In 1997, when Austin was 4, the family was living in San Antonio while Rivers worked for TNT. He was on assignment and playing golf in Seattle when Kris made a last-minute decision to pack up her four children and visit family in Wisconsin. While they were gone, their house burned to the ground.

It was arson, Rivers would later learn, a hate crime driven by race. And Rivers seethed. His home had been destroyed. His family pets had perished in the rubble. His immediate goal was to level the house, clean it up, to protect his wife and children from the horrors of what he had seen. He built them a new home a few streets away and told them, "We will not run from this."

But after the fire, Austin hardly wanted to go outside. When the family planned a vacation, he'd become unglued. The fire had happened, after all, while they were away.

"The other kids rarely talked about it," Doc says. "It affected Austin more than any of the four. We don't know why. You never know why."

Initially, Kris and Doc were tight-lipped about the circumstances of the fire. How could they possibly explain that someone had done this merely because of the color of their skin?

"We didn't go there originally, but they knew," Doc says. "When you go to school, the kids tell you."

He didn't specifically mention Martin Luther King in trying to navigate the complicated burden of race with his young children. Maybe, he says, he should have.

"But my message came from what Dr. King stood for," Doc says. "So much of that involved mental toughness. Austin has needed some of that. He's been called every name in the book -- black, white, Mexican -- he's heard it all."

The father's advice to his son had a familiar ring to it: Turn away. Don't respond. The minute you respond, they win. Grady's advice to Glenn, born from Dr. King's teachings, was now being passed from Glenn to Austin.

Yet Rivers didn't limit his message. He committed himself to making sure his basketball players became versed in the civil rights movement, too.

Paul Pierce recalls Rivers playing the entire "I Have a Dream" speech before a pivotal Boston Celtics playoff game in 2008.

"Doc is very big on reminding us of what Martin Luther King did for black Americans," Pierce says. "He got that from his dad. I never met Grady, but I feel like I knew him because Doc talked so much about him."'

AUSTIN'S GRANDFATHER, GRADY, who affectionately called him "baby," died in 2008 during Boston's championship season. Austin says he didn't realize how passionate his father and grandfather were about Dr. King until he joined the Clippers.

"I don't think there's anybody in sports who is better at giving big speeches before games than my dad, and they usually involve Martin Luther King," Austin says.

The one that resonated with Clippers point guard Chris Paul had to do with knowing when to exhibit restraint.

"Doc talked about when someone antagonizes you and you punch him, you think that shows strength," Paul says, "but as Dr. King always said, it actually shows more strength when you walk away. The toughest guy isn't always the one who puts his fist up."

Last November, during an off day in Memphis, Austin went alone to visit the Martin Luther King memorial. He found himself wondering why our country still remains so unsettled.

The entire Rivers family returned to Maywood in July 2015, when Doc's mother, Bettye, passed away. While they attended her service, a shootout erupted three blocks away.

"My best friend Corey Cooper was at my mom's funeral," Doc says. "He's a cop. He comes to me and says, 'Hey, I gotta go.' I said, 'What happened?' He said, 'Maywood happened.'"

Austin says the persistent violence in Chicago crushes his father. His old neighborhood might be worse than that day in 1968, when Grady spoke to Glenn about Dr. King in his patrol car.

"We used to go there every summer," Austin says. "We'd visit friends and go to family reunions. We don't go anymore because of the violence."

Austin is surprised when people dismiss the idea that race is an ongoing concern.

"People like to say, 'The past is the past,'" Austin says. "They say, 'Oh, the racial stuff is over with.' But it's not. We're still behind. We started so late. Take any race and put them through what African-Americans have had to deal with, and it's going to take time."

Doc Rivers says the movement for racial equality deteriorates into moments where it's one step forward, then one step back.

"But never two steps back," he says. "So that's something. My own personal feeling is, we can't get frustrated. We can't stop working and teaching.

"The election broke my heart, but not because the person I wanted to win didn't win. I can get over the person I supported not winning. But I don't ever like it when there are racial overtones to anything. For a lot of people -- women, minorities, poverty-stricken people -- we hear 'Make America great again.' Make America great -- I'm all for that. It's the 'again' part that scares me."

THE CLIPPERS PLAY the Oklahoma City Thunder on Martin Luther King Jr. Day. Glenn "Doc" Rivers will address his team before they take the floor. He's not yet sure what he will say.

Austin Rivers will refrain from posting a tribute to Martin Luther King on social media on the occasion of his birthday. "I feel like it comes off as unauthentic," he says.

Doc Rivers has been active in sharing the message and values of Dr. King with his family and players. Jerry Lai/US Presswire

Instead, he will take a moment to thank Dr. King for the opportunities he has provided people like the Rivers family.

"Without Martin Luther King, especially someone like me, whose mom is white and dad is black, where would I be?" Austin says.

Sometimes, when Austin drives to the team's practice facility in Playa Vista, he finds himself cruising down Martin Luther King Jr. Boulevard. It snakes for several miles, dotted with beauty supply stores, bail bondsman shops and tired houses in need of a fresh coat of paint. It is one of more than 700 streets in America named after Dr. King.

"Usually streets named after civil rights leaders are in rough neighborhoods," Austin says. "It stinks. It would be nice to have a Martin Luther King Street in Beverly Hills."

His father chuckles upon hearing this.

"Austin's right," Doc says. "We're not there yet."