A third son, Darryl McDonald, 51, had traveled to the funeral from Melbourne, Australia, where he is a basketball coach. “I said, ‘Rich, that doesn’t look like Mom,’” he recalled. “He told me she’d been in the hospital for a long time. She had tubes and all, and her face could have changed. I was like, ‘O.K.’”

No other theory seemed plausible. “You’re in a funeral parlor,” Darryl said. “There is just no way that’s not my mother. You would never think that.”

Adults would not, anyway. Another of Ms. McDonald’s granddaughters said that day that the woman did not look like her, and like Errol McDonald’s son, she had been corrected.

“A child would speak on it,” said Leroy McDonald, 60, a fourth son. “An adult says, ‘I’m sorry for your loss.’ Someone says, ‘That’s not your mom,’ in a funeral home? That would be appalling.”

He thought back to when he first saw the body. “When you look from a distance, it looks like my mom,” he said. “You know what threw me off? The lady had my mother’s clothes on.”

More than 100 people attended the visitation hour before the funeral that evening, and more than that went to the ceremony, Richard McDonald, who officiated, said. He said the first floor of the church, which holds about 200 people, was filled, with others sitting upstairs. Several mourners, himself among them, eulogized the woman in the coffin, recalling Ms. McDonald’s years of service with the United States Postal Service and her raising eight boys in a crowded Harlem apartment.