Aramazd “Piqui” Andressian Jr. went missing on April 21, 2017 after a day at Disneyland with his father, Aramazd Andressian Sr. The father, who was found passed out in his car at a park, said he had taken his son to play before he was to return him to his mother, and he wasn’t sure what happened to himself or where his child was. After a months-long search for the 5-year-old boy, Andressian Sr. admitted to murdering his own child.

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In an exclusive interview with Dr. Phil airing Tuesday, Piqui’s mother, Ana Estevez, shares details she says she learned from authorities about her son’s final moments.

“My son was asleep when Ara began to suffocate him with his own sweatshirt. And I asked the detective ‘Did my son wake up while he was being suffocated?’ And he said, ‘Yes.’ He said that it took Ara about four minutes to murder my son,” the grieving mom tells Dr. Phil.

WATCH: Woman Claims Ex-Husband Who Killed Their Son Made The Child Lie During Custody Battle

Estevez says her son’s body was located in a wooded area near Lake Cachuma, CA. “Ara took my son and propped him up against a tree. He took off a gold necklace that I had given to him the day before we got married and he put it around my son, and he left him there, lifeless,” she continues.

Hear more in the video above, including why Estevez says she believes her ex had been planning to kill their son for months. On Tuesday’s episode of Dr. Phil, hear why Estevez says she believes she was let down by the judicial system. Check here to see where you can watch.

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