Adorable five-year-old boy killed in horror crash returning from church convention with his grandparents

A five-year-old boy was killed by an 18-wheeler when it struck his grandparents' car on their way home from a church convention.

It happened near Matehuala, between San Luis Potosi and Monterrey in Mexico, killing Zachary Reyna just days before he was set to start kindergarten, his family in Texas said.

The child's seven-year-old brother, Malaki Reyna, and a student at the school Zachary was set to attend were also in the car. 

He was not hurt - just left traumatized by what happened, relatives said, as they have since been able to get the boy and his brother's body back to San Antonio.

The accident, a rollover crash, happened the morning of August 4, with Zachary's body arriving five days later. 

A funeral service for the youngster was held last week. His grandparents were taken to a hospital in San Luis Potosi, as the boy's mother frantically drove down to Mexico upon learning of her son's fate.

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Zachary Reyna, 5, was killed by an 18-wheeler earlier this month when it struck his grandparents vehicle on the way home from a church convention in Mexico

The boy was the youngest of three brothers and one sister. He is seen here being held by his mother, Julie Navarro Reyna, surrounded by his elder brothers and other young family members. Also in the car was seven-year-old Malaki Reyna, seen to the right of his mom

'She's just broken,' said Jennifer Navarro, Zachary's aunt, as the boy's grandmother remains hospitalized in critical condition.

'It's hard to hear her voice because you can just hear that she's hurt. 

'Knowing that it's her son, as a mom, you just can't imagine something like that.

'They were coming back from a church convention,' she went on to reveal. 

'On the way over, they had an accident with an 18-wheeler,' she said.

 'It happened near Matehuala, between San Luis Potosi and Monterrey.'

The family member went on to described how both the grandparents, Antonia and Fructuoso Reyna, were taken to a local hospital, where Antonia currently remains to this day.

Fructuoso, meanwhile, was released last week, as cops in the country continue to investigate what transpired.

Zachary, she said, was taken to a mortuary in Monterrey, where his mother after several days was able to arrange his return.  

Malaki wasn’t hurt, 'but he is seven years old and basically saw everything', she said, as the family continues to reel from the tragedy.

'She's just broken,' said Jennifer Navarro, Zachary's aunt, as the boy's grandmother remains hospitalized in critical condition

'He was about to start kindergarten at Collier Elementary,' Jennifer said of Zachary. 'He was excited, just like all kids are. He was happy and wanted to follow his brothers everywhere and do what they are doing'

The rollover crash happened near Matehuala, between San Luis Potosi and Monterrey, in Mexico, and remains under investigation

'He was about to start kindergarten at Collier Elementary,' Jennifer added of Zachary.  

'He was excited, just like all kids are. He was happy and wanted to follow his brothers everywhere and do what they are doing.' 

His elder brother, she said, was still recovering at home, but was well enough to attend Zachary's funeral service this past Thursday.

He, along with other young family members including his own elder brother, served as pallbearers.

'Today Zachary was laid to rest,' a relative wrote in one of two GoFundMe's started to help the family and address funeral costs that have collectively received nearly $40,000.

'No words can describe the pain, grief, disbelief Julie & Family have enduring through this difficult time. 

'[Zachary's] Celebration of Life was beautiful and heartfelt. 

'Without your pouring continuous support, Julie would had not been able to bring her baby home and laid him to rest with the angels in the kingdom of God.

A funeral service was held for the boy on Thursday, after his mother drove down to Mexico to retrieve him

'Today Zachary was laid to rest,' a relative wrote in one of two GoFundMe's started to help the family and address funeral costs. 'No words can describe the pain, grief, disbelief Julie & Family have enduring through this difficult time... Thank You for making a difference'

'Julie & boys have a long journey with guidance and the ability to deal with the darkest feeling of grieve. May God lift their hearts with love and peace.

'Thank You for making a difference in their lives.'

The crash, as writing, remains under investigation. The condition of the driver of the 18-wheeler was not made available.