Steven and Elke’s 3-month-old son, Lucas, died in 2020. The coroner determined that the infant’s death was the result of a subdural hematoma, consistent with shaken baby syndrome, and ruled it a homicide.

“Someone had to have shaken Lucas because there’s no other way those injuries could have happened,” says Steven, who says he is currently the subject of an investigation into the baby’s death. He adamantly denies hurting Lucas and says he is heartbroken by the loss of his son.

“I don’t think Steven was capable of harming our son,” says Elke.

Steven’s mother, Melissa, also insists her son could not be responsible for Lucas’s death. She claims that all the evidence points to Elke and says, “What I said to Elke is, ‘If you let Steven go down for something we all know you did, I’m coming for you.’”

Steven says he is “100%” certain there is no way that Elke could have injured Lucas, so why is Melissa claiming she did?

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?’,” Dr. Carole Jenny, Director of the Fellowship Program in Child Abuse Pediatrics at Seattle Children’s Hospital joins the conversation.

Check local listings to find out where you can watch.

WATCH: Woman Claims The Mother Of Her Dead Grandson ‘Seemed Relieved’ After The Baby’s Funeral

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