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DALLAS (CBS 11) — 28-year-old Joshua Allen was arrested for manslaughter after police say he was speeding, ran a stop sign and slammed into a car carrying a young mother and her little boy Friday night.

The 19-year-old mother behind the wheel was bruised from the impact. But her son, 2-year-old Noah Vasquez, was in the back seat when the truck crashed into the rear driver's side. Investigators say the boy was next to his child safety seat, but family members say he was sitting in it.

Police say Allen was driving northbound on Duncanville Road and ran the stop sign at the intersection with Ledbetter Drive when he collided with the victims' car. Now the victims' relatives tell us they're outraged after learning this is far from the suspect's first trouble with the law.

In his brief life, 2-year-old Noah Vasquez made a lasting impact on his extended family.

"Life without Noah now is not going to be the same anymore," Noah's great-grandmother, Angie Salazar, said.

Salazar was his regular babysitter. She says the boy's mother, 19-year-old Sara Casillas, was on her way home to the family when her car was hit just a block up the street.

"I don't know how we're going to move on from this. I don't know how to live again or from this. I don't know how because Noah was such a big part of our life every day," Noah's grandmother, Priscilla Martinez, said.

Police took Allen into custody after the crash. A criminal background search on Allen reveals a history of charges including assault, DWI, and burglary.

"I want the court system to finally lock him up for a long time, for life," Salazar said, "He doesn't deserve to be out. That's what I want. I want justice."

Now Salazar says members of her family plan to keep watch over this case as it makes its way to the courts.

"We're going to be there at every court date. We're just going to be there, and we're going to make sure that they hear us 'cause Noah... He's not here, but we need to speak for him," Salazar said.

A funeral for Noah Vasquez will be held Wednesday morning. If you'd like to help the family, they've set up a GoFundMe account.

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