Photographer captures powerful moment of tearful black mom with her son at protest

A Chicago photographer's photo of a black mother and her baby boy is touching people by the thousands.

Amber Marie Green told "Good Morning America" she was up at 5 a.m. on Saturday. Something was telling her, she said, that she should take photos of the protests near the Chicago Federal Building.

"I got there right before people started gathering," she said. Within a short time, she said, thousands of people had gathered. Cars with "Black Lives Matter" and similarly supportive signs were arriving in droves.

"I was snapping away and I saw a woman driving a car. I looked in the backseat and I saw a mother, holding her son, encouraging the baby to look at protesters with tears running down her face. We locked eyes, raised our fists and gave a nod. We both knew," she said.

The woman in the photo is D'Asia Hervey. She brought her 8-month-old son, Matthew, to the protest at the encouragement of her mother, Stephanie Woodall Wilson.

"I told D'Asia to raise him up to the camera," she told "GMA." Matthew's grandmother said he was the youngest protester present Saturday.

"I want D'Asia to understand why I was so worried and paranoid about her and her brothers," Wilson said. "There's a reality Matthew will have to deal with."

Green said that she has an 11-year-old son herself.

"I know what those tears meant," she said of Hervey's emotion. "Black mothers have to think about 'the conversation' they will have to have with their sons. We tell them, 'When -- not if, when -- you are detained by the police, do what they say. Keep your ID on you. All we want is for you to come home alive.'"

Hervey said she remembers the moment Green snapped the photo of her with Matthew in the car parade.

"I wanted him to see all the people coming together, protesting and fighting for his future so he doesn't have to be a target," she said. "I raised his little fist up. I don't want to bury my son."