The little boy's mother was shopping at a garage sale. He was playing, steps away, in the front yard.

Another shopper had parked her pickup so that it straddled the yard and street. She started to drive away.

And in the blink of an eye, the toddler's head was under the truck's front passenger tire.

"The mother was screaming in Spanish," witness Darius Wiley said Sunday. "She was saying 'Get off!' 'Get off!' "

The pickup rolled forward. Celia Hernandez, mother of 1-year-old David Hernandez, scooped up the mortally wounded child.

And the truck kept going.

"She was barely rolling, like she didn't hit the gas," Mr. Wiley said. "She didn't speed off. It's like she was in shock."

Now Dallas police are searching for the driver, with little to go on. Descriptions of her are sketchy. The truck was gray or silver, witnesses said. A license plate number that one person wrote down didn't check out.

The accident occurred about 12:30 p.m. Saturday on Pleasant Vista Drive, near the intersection of Elam and Masters drives in Pleasant Grove.

David was taken to Baylor University Medical Center at Dallas and then Children's Medical Center Dallas, where he died late Saturday afternoon.

Doctors had told his family there was little hope because of two skull fractures.

On Sunday afternoon, relatives solemnly remembered the toddler's short life as they stood outside their mobile home in far southeast Dallas.

"He cried very little," said Hector Hernandez, David's father. "He was always smiling. He liked to live a lot. I miss him a lot."

A bright pink and purple Jeep toy, a Dora the Explorer bike and a tricycle dotted the yard where David used to play with his toys and run around with his uncle Mario Gonzalez.

"He was too young for this to happen to him," Mr. Gonzalez said. "I wish this thing could've happened to me instead of him."

He pleaded for the driver to surrender.

"She's going to get herself in more trouble for running away," Mr. Gonzalez said.

Mr. Hernandez, who also has a 5-year-old daughter and 3-year-old son, tried to make sense of why the driver fled.

"She could've stopped; she could've helped," he said. "If she had stopped, maybe things would have been different."

Mr. Hernandez said he wants the driver to face her mistake.

"She hurt a little angel," he said. "She's hurting an entire family."