Missing Isabel Celis' parents appeared on Katie Couric's talk show, "Katie."
The episode, "Vanished: Gone without a trace," aired on Monday, December 3. Isabel has not been seen since vanishing from her Tucson home in April 2012.
Last seen on Friday, April 20, it is believed she disappeared from her room sometime after 11 p.m. that evening.
Becky and Sergio Celis told Couric that they believe that Isabel's abduction was not a random act and that it must have been someone that had been inside their home.
Sergio and Becky told Couric that knowing details like their big dog outside was deaf and that their "yippy" dogs were inside their room, on the opposite side of the house from Isabel's bedroom, were proof that Isabel's abductor knew their home.
"It had to have been someone that was in our home one time or another," Sergio said.
Sergio was the one who discovered Isabel was missing the morning of April 21. He told Couric that he initially thought that maybe she was out to breakfast with a family member, "something logical," he said.
Police have not ruled out anyone as a suspect. Becky said to Couric, "They can't rule anything out until Isa comes home…when she comes home everyone will have their answers."
When Couric asked about the results of their polygraph tests, Sergio and Becky said that they were not allowed to discuss the results due to the investigation and that police "didn't even really discuss it with us," Sergio said.
On not being allowed to see his son's for two months, Sergio told Couric it was "indescribably horrible." "We were already broken and they were trying to break us more," said Sergio.
Becky says she has a motherly instinct that Isabel is still alive, "I know she's okay out there," she told Couric.
To watch the full interview from Couric's show click here: http://bit.ly/QK3XYz
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