Dr. Caroline Moniza, at Mercy Medical Care in Cedar Rapids, specializes her work around children with autism.

“Seven to 10 that is an age group that tends to wander away but then there's also there is a big percentage of that group that will continue to wander as they get older."

She says just because a child wanders doesn't mean there's a lack of adult supervision. Usually the child is looking for a calm spot, where he or she won't be in sensory overload.

"They do tend to be drawn towards water."

16-year-old Jake Wilson was last seen walking to a nearby creek. Both authorities and family members are still unsure why he never returned home.

"What's going on, where's he at why? What's happened? There's something we don't know about. You're not really well informed, everybody isn't, as far as what's going on,” Jake’s grandpa, Bruce Wilson said.

Authorities did expand their search on Tuesday, now going eight to nine miles outside of LaPorte City. And this follows the National Autism Association's guidelines, about what to do in missing children cases.

The association says children with autism are known to walk several miles outside of the established search area. Often these children will hide in small spaces.

And experts say if searchers come in contact with a child with autism they will likely face communication barriers.

"I think it’s more difficult with children with autism because they don't always have the communication abilities to be able to respond to their names being called or letting people know they need.”