"Jerilynn's not telling the truth," he said.
We contacted St. Cyr about that statement and she started crying, said "no comment" and hung up the phone.
Sylvester maintains that cocaine dealers he owed $4,000 to $4,500 entered his "doghouse" apartment on Father's Day, murdered 7-year-old Randy, Jr. and 3-year-old Denim, stuffed them in a suitcase and wooden trunk, dumped them in the woods and set them on fire.
"Anybody would kill anybody over $2," Sylvester said.
When we asked how he then led police to their remains, the father said because of past drug deals he had, "a hunch."
He insisted his common-law wife did not know anything about the killings despite not calling police for six hours after they disappeared. He said her 911 call on Sunday was genuine.
Operator: "Why did you just decide to call us now?"
St. Cyr: "Well, I thought they were with a friend and I'm waiting for the friend to come home."
He also maintains that she was unaware that he owed dealers money.
But the mother has now been subpoenaed to appear before a grand jury. However when Eyewitness News questioned St. Cyr about the legal matter she said quote, "No one has talked to me about anything. I don't know how all of this works."
Sylvester acknowledges that his story was hard to believe. "It's hard for me to believe," he said from the Harris County Jail. "My kids are dead because of me."
Sylvester said he has been a drug dealer, but not a user, for a long time, but only for about a year with the dealers he claimed killed his children. He said it "was nothing new" for drug dealers to kill family members when deals go bad.
"It's part of the game," he said.
He said neither he nor his wife use drugs.
"I wish it would have been me," said Sylvester, who added God knows the truth.
Sylvester said had not yet heard from an attorney and is charged with two counts of capital murder.
Wednesday night, Texas Equusearch will host another memorial for Randy and Denim Sylvester. It's at 7pm at the Gateway Community Church. That's on Clear Lake City Boulevard in Webster.
MORE DEVELOPMENTS: Mother reportedly subpoenaed
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