CHARLOTTE, N.C. -- The National Center for Missing & Exploited Children is expected to release an age progression photo of missing teen Erica Parsons, likely by the middle of the week.
The organization put Parsons' picture on its website Friday, but has not received any tips, according to center officials.
Meanwhile, Parsons' adoptive parents Casey and Sandy are scheduled to be on the Dr. Phil show and tell their story to the nation Tuesday and Wednesday. The show's website says Wednesday's airing includes a polygraph test.
Family attorney Carlyle Sherrill says he is aware of the polygraph test but is not revealing the findings prior to the show airing.
Erica is listed at 4-foot-5 and weighing 85 pounds when she went missing from the family home on Miller Chapel Road in Salisbury in 2011. At the time, she was 13-years-old.
The new photo will show what Erica is expected to look like now, at 15-years-old.
"Two years is an awfully long time for us to be delayed in searching for this child, so I asked them to put a rush on it," said center spokesperson Bob Lowery.
They received Erica's picture Friday as well as photos of her biological parents. The center is using them to come up with the new picture.
The hope is the picture generates tips or leads them to Erica.
"The more exposure that gets out there in front of the public, it helps spark some of the memory that they may have seen the child, even if it was back a couple of years ago, that's ok," Lowery said.
The center also has a case team assigned to help investigators.
Time is an enemy searching for missing child.
The center says if something bad happens to them, it's typically within hours of a disappearance.
"The longer this goes on, the least likely it is we are going to find them," Lowery said.
But not impossible, Lowery said, using three girls found in a Cleveland house a decade after they disappeared as an example.
No one has been arrested or charged in Erica's disappearance. Erica's parents, Casey and Sandy Parsons, deny any wrongdoing and say Erica decided to live with her biological grandmother in the Asheville area after an extended holiday visit.
Investigators aren't saying when they'll know the results of red stain samples and wall swabs taken from the family home during last week's search.
There's a lot of interest in this story, so NBC Charlotte has created a page on Facebook dedicated to the search for Erica. Http://www.Facebook.com/EricaParsonsUpdates