Mario Sanchez said a medical diagnosis and a manipulative ex-wife kept him in the dark about the danger.
Sanchez said he loved his son beyond words, dreamed of what he'd grow up to be, and considered him his best friend. Sanchez said he's seen questions circulating online about his whereabouts in the days and weeks before his son's killing. He said he wanted to share his story with ABC13. He remembered Jason as a happy kid who loved to dance and sing, play with his toy cars and games.
He said he did everything in his power to be with his children.
The murder of Jason Sanchez-Marks made headlines last week. Police arrested his mother, Ashley Marks, for capital murder. Prosecutors accuse her of overdosing Jason to death on cocaine, meth, and NyQuil in order to cash in on $100,000 worth of life insurance money.
SEE ALSO: Mom accused of causing 6-year-old son's drug overdose for $100,000 life insurance payout
The boy died on June 27, 2020 after enduring hallucinations, projectile vomiting, and sleeplessness for days, according to a report filed with the Texas Department of Family and Protective Services. The same report said both Jason and his sibling had been receiving medication for tuberculosis.
Sanchez said he believes his ex-wife should face the death penalty if convicted.
"I'm asking this too. I would like to ask Ashley why did she do all this? Jason loved Ashley so much," said Sanchez. "There are many questions I would want to ask her. Why did she do it? Why didn't she ask for help, for money?"
Sanchez said in early 2020 he tested positive for tuberculosis. He spent two weeks in the hospital, violently ill, including spitting up blood. Sanchez said the diagnosis led to home isolation orders from the City of Houston Health Department.
"I went to the hospital two times," said Sanchez. "The last time I got to the hospital. I stayed there for two weeks. I was really sick. I was spitting blood. I (didn't) see Jason and (his sister) because I was sick."
SEE ALSO: Daycare worker says mom accused of killing son 'deserves everything coming her way'
The Health Department told ABC13 they cannot provide information about any tuberculosis cases as it would violate patient confidentiality. They did say part of a patient's treatment could require a person to remain in home isolation until they determine they are no longer infectious.
Sanchez said in addition to the order, his ex-wife lied to him about their children's whereabouts and actively prevented him from seeing the kids. Sanchez said Marks would claim she was sick, out of town, or the children were at a friend's place.
"I had all these text messages. Where's Jason?" said Sanchez. "I tried to contact her many, many, many times."
Sanchez said eventually he saw his son and daughter at Marks' father's house the Thursday before Jason's murder. He said Jason appeared happy and healthy. He said after that day he lost all contact with the ex-wife and grandfather until his son's death.
Sanchez said neither Marks nor her father ever told him Jason started to fall ill.
"All the time I worry for my kids ... they're never telling me that Jason is sick. They're never telling me he's sick," said Sanchez. "I do whatever I need to do for my kids."
Sanchez said the loss has left him devastated. He's been actively posting to Facebook hoping to raise awareness about his son's case. In video after video posted to his page, you can see Sanchez interact with his son in a loving fashion.
"She needs to pay for everything," said Sanchez ."She needs to pay ... I'm sure she did it for money. She did it for one reason. She wants the money."
SEE ALSO: Dad says mom accused of overdosing 6-year-old for life insurance was 'thirsty for money'
Ashley Marks' father has declined multiple requests from Eyewitness News for an interview about his grandson's death. He said he couldn't offer ABC13 any comment for our reporting.
She is due back in court on Friday, April 16. A judge will decide whether she'll be given bail.
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