Steven says he is currently the subject of a homicide investigation for the May 2020 death of his infant son, Lucas. He adamantly denies causing the brain injury that led to Lucas’s death and says he doesn’t believe that his girlfriend, Elke, hurt their baby either.

“I do believe that someone had shaken him, and I don’t know if it was on purpose or if it was an accident, and they were too scared to say something,” he says, suggesting someone else may be responsible for the baby’s fatal injuries.

How does the couple explain why, on discovering that Lucas was unwell, Elke didn’t wake up Steven and decided to take her son to the hospital by herself?

Part one of this two-part Dr. Phil, “’My 3-Month-Old Grandson Was Murdered; Who is To Blame?’” airs Thursday. And on Friday’s conclusion, “’Who Killed Baby Lucas?’,” does the couple say that anyone else had access to baby Lucas in the hours and days before he was hospitalized?

Check local listings to find out where you can watch.

WATCH: Man Who Says He Is Under Investigation For Baby’s Death Claims Doctors Told Him His Son Also Had Older Injuries

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