NEW YORK — They are small figures moving through a subway station on a Saturday in Manhattan — a mother and her son speaking softly to each other in Burmese.

Than Than Htwe, 58, is a homebody, content to stay at her family’s Brooklyn apartment on the weekend meditating or simmering fish in a pot of lemon grass and ginger. But she scheduled a doctor’s appointment for this morning so it would not conflict with her job stitching custom aprons.

By Htwe’s side is her only child, Kyaw Zaw Hein. At 22, he carries the hopes of his family on slight shoulders. His parents waited more than a decade in Myanmar for a visa so he could attend an American university. They arrived just three years ago.

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Hein stays close to his mother as they climb the stairs that lead to Canal Street in Chinatown, where the July sun waits. He feels protective of her and looks forward to the day when he earns a salary that provides for all of them.

The landing is in sight when Htwe urges her son to “run up.”

Perhaps she is merely trying to hurry them along. Perhaps she has seen the man behind them with the angry eyes.

Hein attempts to quicken his steps, but he feels a hand bearing down on his blue backpack that then yanks him off his feet until his body is falling. He does not know that his mother has somehow also been forced backward, that she is tumbling down the stairs, that her head has smacked against the tile floor.

When his eyes adjust, he is on the ground, his backpack still on. The man who pulled him down is hovering nearby, a look of disdain on his face. For a moment, Hein worries he will be hurt again. But then the man disappears into the station.

Htwe lies on the ground, her eyes half open. Her son shakes her shoulders, calls to her, tries to cradle her head. That is when he sees the blood in her dark hair, drops of crimson on the ground. He clasps her hand. And screams.