“He wasn’t so satisfied with life here,” Ms. Zhang said of her son. “He was so tired here, and there wasn’t so much money.”

Not a day went by that they did not miss their hometown, Ms. Zhang said. But until this past winter, they had never returned for a visit. They wanted to save the cost of train tickets.

They live in bare concrete rooms on the ground floor of an apartment block opposite the market. The kitchen has a makeshift two-burner stove a few feet from the parents’ bed. Most of their neighbors are fellow settlers from Henan and Sichuan.

At the market, about three-quarters of the 200 vendors are from those two provinces, the parents said. A handful of Uighurs sold fruit or raw mutton.

“Relations with the Uighurs were pretty good,” Ms. Zhang said. “There was a mutton stall beside the cart where my son sold fruit. On nights when my son didn’t want to bring his fruit home, he would ask the Uighur neighbor to keep the fruit inside his stall.”

This past winter, the family took the nearly 40-hour train ride home for the first time. The parents had arranged for Mr. Lu to marry a 23-year-old woman from home. The couple had photographs taken: Mr. Lu in a white turtleneck lying beside his bride-to-be in front of a beach backdrop; the smiling couple sitting on a white bench, each holding teddy bears in their laps.

The family returned to Xinjiang after scheduling the wedding for the end of this year.

On Sunday, as on any other day, Ms. Zhang, her son and a young cousin pushed four carts to the market. Mr. Lu’s father had gone to another province to buy fruit wholesale.