A psychologist said even if Ethan appears to be doing well on the outside, he needs to talk out what happened to him. Hoping the 5-year-old will forget what happened would be a bad strategy, said Wendy Walsh.

"That's not actually good because when you start to forget, some traumatic events they get stored in your body as feelings that crop up at strange times in your life," she said. "It is better to process it, get some therapy."

Someone who knows all too well what Ethan may go through is Katie Beers, who as a 10-year-old was held underground in a concrete bunker for two weeks by a New York man.

"I am ecstatic that Ethan has been retrieved safe and sound," said Beers, who recently released a book about her abduction. "As for my ordeal, I just keep thinking about the effects of it: being deprived sunlight, nutritious food and human contact. And how much I wanted to have a nutritious meal, see my family."

Beers says she still feels the effects of her kidnapping.

"The major issue that I have is control issues with my kids and finances," she said. "I don't like my kids being out of my sight for more than two seconds. And I think that that might get worse as they get older."