Prosecutors read for the first time in public the court documents detailing the probable cause they have for prosecuting him.
On June 15 at about noon, the day the children vanished, prosecutors say Sylvester made a mysterious request. Two friends he was subleasing an apartment to say he told them to leave.
When they came back four hours later, Assistant DA Stephen St. Martin says they noticed something strange.
"There was an order of cleaning supplies and the windows were open," said prosecutor Stephen St. Martin.
Those two ewitnesses say they also realized a trunk that was in that apartment was now missing. Investigators say that trunk was located in a wooded area of southeast Houston. Almost a week later, it was burned, as was 7-year-old Randy Sylvester, Jr.'s body, which was inside.
The boy's father led authorities to those remains and those of three-year-old Denim. Authorities say her body was burned in a suitcase an eyewitness says her father put in the back of his car on the very same day the children went missing.
In a jailhouse interview, Sylvester tells Eyewitness News his children were killed over a debt he owes a drug dealer. He said he wished he was dead instead.
Sylvester's newly appointed attorney characterizes his client as depressed.
"I think anybody would be if they had the media outside the courtroom and everybody was looking at him," said Jerome Godinich, Sylvester's court-appointed attorney.
Prosecutors can't say yet if they'll seek the death penalty against Sylvester. They do say they want to ensure justice is done and that includes Sylvester's right to a fair trial.
"We're approaching it with everything we have," said St. Martin. "We're going forward."
The autopsies on the children are not yet complete. They'll help determine something we still don't know, if the children were killed before they were burned or if they were burned alive.
MORE DEVELOPMENTS: Mother reportedly subpoenaed
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