Ana Estevez’s 5-year-old son, Aramazd “Piqui” Andressian Jr., was murdered by his father in April 2017. Estevez, who was in a bitter custody battle with her ex-husband, says she tried going to the courts multiple times with her concerns about her ex’s behavior, but she says her claims fell on deaf ears.

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The grieving mom tells Dr. Phil in an exclusive interview airing Tuesday that she now feels like she let her son down.

WATCH: Mom Whose 5-Year-Old Was Murdered By Her Ex-Husband Recalls Last Conversation With Son

“As much as I want to tell myself that it’s not my fault, I still deal with the ‘what if.’ I did everything I could possibly do to protect my child, but in the back of my mind I just, I still think of what else could I have done? What did I do wrong?” Estevez says. “I have apologized to my son so many times for failing him.”

Watch part of her interview in the video above, and tune in to Dr. Phil on Tuesday for the entire interview. Check here to see where you can tune in.

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