Transcript for 16-year-old Amy Yu found in Mexico

Next to the latest in the search for 16-year-old Amy Yu. Police said she was dropped off her bus stop 12 days ago but never end up at class. She ended up on on a flight to cancun with 45-year-old married man. What we're learning tonight about that investigation. Reporter: New details emerging tonight about the disappearance of 16-year-old Amy Yu and 45-year-old Kevin Esterly as authorities in Mexico issue an amber alert. The two vanishing on March 5th, police say the married father of four, flew on one-way tickets from Philadelphia to cancun. All information received thus far leads investigators that she left Allentown willingly with Esterly. Reporter: Tonight, his wife's Stacy speaking through her attorney. Telling ABC news that she was concerned about the relationship. Stacy told Amy's mom that this relationship was unhealthy. It was more than a pseudofather/daughter relationship. Reporter: Yu's mother going to police after discovering her daughter allegedly changed school records to claim Esterly as her stepfather. Police advising Kevin and Stacy to stay away from the teen. Her family pleading for her safe return. I love you. Can you come back? Tom, if captured he could face a third degree felony charge of interfering with the custody of a child. Now to that dangerous

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