FORT WORTH (CBSDFW.COM) – Mary Delgado will be laid to rest on Friday.

Her Fort Worth family meanwhile, remains tormented.

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The 26-year-old single mother was killed in a hit-and-run crash in rural Collin County last weekend.​

“She was a sweetheart,” shares her brother, Dominic Delgado. “She did everything for her two children.”​

Mary Delgado (credit: Delgado family)

A rural road just south of Princeton set the scene for such heartache.​

“Her kids witnessed their mom being killed right in front of them,” says friend Cierra Garcia. “Now they’re left without a mom.”​

Left on the roadway, shards of broken glass, most likely from the fleeing vehicle’s headlight.

Broken headlamp from deadly hit-and-run (credit: DPS)

The fragments mirror a family of shattered hearts.​

“We had to tell them,” says brother Dominic Delgado, of breaking the news to his young nephews who are 9 and 7. “And it was the most terrible, worst thing we’ve ever had to do.”​

Relatives say Mary Delgado had gone to celebrate the Fourth of July holiday with friends in the rural area so that the kids could pop fireworks. ​

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“All we heard was a big bang,” recalls host Mariano Garcia. “Kids went running in the house and started hollering.”​

According to Texas Department of Public Safety investigators, whoever struck her didn’t bother to stop. ​

“We just want them to come forward. We just don’t understand,” says Dominic Delgado, his voice breaking. “If it was an accident, okay, say what happened and come clean.” ​

Family members say the selfless, always positive Mom managed to speak a few words to her 9 year old son before the ambulance took her away.​

“She told him that she loved him so much and to be strong,” says sister Yvette Garcia, the tears beginning to flow. “That it wasn’t their fault, to be very strong for her.”​

According to DPS investigators, “a vehicle was traveling east in the 7500 block of Lucas Branch Road between the Lake Lavon Bridge and FM 982. It’s believed the vehicle continued east and turned north on FM 982.”

The agency’s release went on to say that “the vehicle involved may have damage to its front, including damage to one or both headlamps.”​ They’re asking body shops in the area to be on alert and contact them if they see something suspicious.

Meanwhile, there is no closure for the grieving family, but they are pleading with the stranger who fled the scene to give them peace. ​

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“I don’t understand,” says Dominic, his voice breaking as his eyes filled with tears. “It just gives me so much anger and frustration, but ​we are praying. We have faith in God that he will give us those answers.”​