A Texas father has been charged with murder more than year after his 6-week-old twins were found dead.

Massail and Mirena Vega were found unresponsive and pronounced dead on October 4, 2023, just before 11:30 a.m., as CrimeOnline reported. Fernando Vega told investigators he was the last person to see them alive, somewhere around 5 or 6 a.m.

The twins’ mother, Angelina Calderon, said she saw the girls in their bassinet that morning but didn’t wake them because she was on her way to work. Vega left the twins in their grandmother’s care while he took Calderon to work and found them not breathing when he returned.

He called 911 and followed dispatchers instructions for CPR, but the twins, who were born prematurely, did not survive.

Officers saw no visible signs of trauma initially, but an autopsy found that they died from blunt trauma injuries. Investigators also learned that the twins had not received checkups since their release from the hospital after the premature birth. Calderon admitted the girls had been sick, but she said she did not seek medical care.

Court documents say that x-rays found the infants had multiple fractures, including to the thigh bone and ribs and the clavicle of one of the babies. Doctors who conducted the autopsies said the injuries appeared to be a mix of new and old — or as old as they could be given the babies’s age.

Both Calderon and Vega were charged in April with two counts of injury to a child.

According to KHOU,  court documents show that Vega’s charges have been upgraded to capital murder. Calderon still faces only the injury to a child charges.

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[Featured image: Fernando Vega and Angelina Belinda Calderon/Houston Police Department]