Roxanne Lewis-Randall claims that she woke up at 2 am to what she says she thought was the sound of her 19-month-old toddler, Lincoln, coughing as he slept in the bed beside her. After going to get him a bottle and some medicine, she says she returned to her bedroom to discover the boy’s eyes were wide open and what she’d thought was coughing was actually gurgling.

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Roxanne says she yelled at her boyfriend, Bert Franklin, to call 9-1-1. “And he stood up at the other side of the bed and just stared at me. At that moment, I thought that it was – some people freeze up in emergency situations – like a panic. So I yelled at him again. I said ‘call for an ambulance.’” She says it dawned on her then, that help might not arrive in time – so she had Bert drive them to the hospital.

On Monday’s Dr. Phil, Roxanne describes the events surrounding the night in July 2016 when authorities allege Bert Franklin fatally injured Lincoln. Prosecutors accuse him of causing a blunt force trauma to the toddler’s head that left him with a fractured skull. The Oklahoma dentist, who denies he harmed the boy, has been charged with first-degree murder. His trial is tentatively set for September 2017.

When does Roxanne say she grew suspicious of Bert’s alleged role in the child’s injuries, and what does she claim Bert did next?

This Dr. Phil exclusive airs Monday. Click here out where you can watch the full interview.

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Mother Of Toddler Says She Believes Her Boyfriend Inflicted Fatal Injury. What Led To Her Suspicion?