SAN DIEGO -- Could you spot a missing child even if he or she was standing directly in front of you?

Every year thousands of children are reported missing.

Finding them could come down to paying attention to the smallest details.

Sometimes a quick glance is all you get in the grocery store or the park.

A missing child could be standing there right under your nose.

If you thought you spotted a child in danger, would you approach or even call for help? Would you even notice?

In November 2003, a young girl from Utah named Elizabeth Smart had disappeared. Her abduction captured the nation's attention. No one expected her to show up at a Thanksgiving meal in San Diego -- least of all 10News reporter Fred Blankenship.

Smart was somewhere in the community concourse with her kidnappers looking for a meal while Blankenship covered the story.

Blankenship missed her. He wasn't expecting to see her, but could he have been more aware? Could you?

"This is what you want to look for -- something distinct and personal to that particular person," said private investigator Dennis Bammann.

Bammann is paid to pay attention to the details. He helped 10News in a test on the powers of observation.

Gerren Hall and Portia Reinhltz are young models from the John Robert Powers Modeling Agency. With their parents' cooperation, 10News put their faces on fliers, posting them in plain sight, and Hall's mom helped by passing them out.

They wandered around the park and were over and over again ignored and missed.

Hall's poster-sized picture was almost as big as a map directory. Everybody saw the map, but not Hall.

After receiving the flier, one mother gave her son a kiss.

Another mother did see Hall.

"If I had believed it was him, then I would have definitely called," said the mother.

10News photographer: "What if I tell you that was him?"

"Oh my God, are you serious?" said the mom.

Reinhltz was found more quickly.

A couple had seen her walking around. Even after seeing the flier, they didn't make the connection.

"Oh my God, I thought we were looking, and we weren't looking," said Laura Macias.

"When you point it out now, it clicks. I should have noticed. We should have noticed," said Jose Becerra.

But the one thing you may never notice is abuducted children acting as if they've been abducted.

"According to the 2004 stats, there were 51 stranger abductions in California and over 2,000 family abductions," said Deputy District Attorney Stacey McReynolds.

McReynolds said even if you're not sure, make a call to alert the police.

"The phone call is critical. It's a win-win. If you call and the child is found, then you're doing something good. And if they're not found, at least (police) have an area to look in," said Bammann.

After two long hours, Hall was finally found by 8-year-old Max Suchman.

"Then I told my mom, and she said, 'No, it couldn't be,' and then I said, 'No, it's him,'" said Suchman.

But Hall's dad is concerned. Why did it take so long?

"It makes you wonder, are we really looking? Do we really look? I'm going to be more on point because I can see what can happen and what does happen," said Edward Hall.

To learn more about helping missing and exploited children, go to www.MissingKids.com.