He read birthday cards and carefully tucked them away; his gifts were unopened as he headed out for work.

His mother would see him later that afternoon, 31 years to the day he was born — bleeding onto the scorching asphalt.

Lewis was on foot, helping another driver clear debris from the road, when he was struck by a pickup, police said.

A passerby found his phone and called Lewis’s father, relatives would later say.

Lewis’s mother rushed frantically to the scene, but authorities kept her away; the last words she could hear her son say lingered after the ambulance roared away without her.

“Momma, momma, momma! I want my momma!” Lewis cried out, his sister told The Washington Post.

He was pronounced dead at Byrd Regional Hospital in Leesville, authorities said.

Soon thereafter, the family learned of a racist Snapchat discussion about Lewis that was circulating online, prompting outrage and calls for justice.

Local police said they were “pretty confident” the chat involved Matthew Martin, the white 18-year-old who, authorities said, killed Lewis with his truck.

In the Snapchat conversation, an image of which was published by ABC affiliate KBLC, a poster using the name Matthew Martin said he had hit “some n—-r” on the highway.

An unidentified person asked Martin how his pickup fared.

“F—-d it up pretty good,” Martin responded, according to the image.

The other person suggested the damage could be buffed out, and asked if Lewis had been killed on impact.

Using a laughing icon, Martin said the man died on the way to the hospital.

The Washington Post could not independently verify that Martin wrote the Snapchat messages. But Chief Deputy Calvin Turner of the Vernon Parish Sheriff’s Office told The Post that “all indications” point to Martin’s involvement in the social media conversation.

Martin could not be reached for comment.

He is not being held and has not been charged with any crime, Turner said.

“I am appalled at the content of the social media messages that were posted after the incident,” Vernon Parish Sheriff Sam Craft said in a statement. “This post is unacceptable and has no place in our society.”

But Craft added that the posts did not violate any Louisiana laws.

The investigation into the deadly incident is being conducted by the Louisiana State Police.

Shotoya Lewis-Ayers said her brother — known as Rell to family and friends — was quiet but kind, offering a sharp haircut and wise advice to the young African Americans who visited Sonny Boy’s Barber and Beauty, which he had taken over after his mentor’s death.

Lewis-Ayers and her brother were “inseparable” as children, she said, a year apart but possessing a twin-like bond. Their parents met while serving in the Army, and they moved from Germany to South Carolina, before their father retired in Leesville, outside Fort Polk.

The family arrived at the scene the day of Lewis’s death.

They looked for skid marks and did not see any. They believe Lewis could have been struck intentionally, Lewis-Ayers said.

State Police spokesman Scott Moreau declined to say whether skid marks had been found or if any other information indicated if the collision may have been intentional.

As the Snapchat exchange circulated, #JusticeForRell trended on social media. But Lewis’s relatives want his legacy to be more than another signpost of intolerance.

“I don’t want people to focus on that racial slur,” his sister said. “I want people to remember for who he is and what he stood for.”

And what did he stand for?

He was a wide-grinned, supportive member of the community, Lewis-Ayers explained, with a big bag of quarters at the ready to buy candy for young customers in his barber’s chair. When they grew older, he attended their basketball and football games, and proudly saw them off to college.

Lewis had no children of his own, but he loved his niece and nephew so fully, people in town often mistook him for their father, Lewis-Ayers said.

And he stood for doing the right thing, Lewis-Ayers said, without hesitation. It was a broiling Louisiana summer day, and Lewis still pulled over to ensure no one got hurt by roadside debris.

“It was no surprise he was going to go back and help as his last deed on earth,” she said.