PITTSBURGH -- Mary Ellen Greacen is mom to 10-year-old Alec and 8-year-old Ian.

Her boys love spending summer days at Camp Deer Creek.

Ian is always on the go, taking part in every activity.

Alec enjoys riding horses and playing board games.

While the boys' interests are different, they have one thing in common; both are autistic.

As an infant, Alec was developing normally, but suddenly everything changed.

Greacen said, “Right about 24 months, he wouldn't touch his sandbox, he wouldn't make eye contact, he wouldn't eat the things he used to eat, we knew there was something wrong.”

The Greacens took Alec to their pediatrician, but he didn't seem worried.

She said, “The pediatrician we had then basically said no, its fine. There was no speech development, but he said just wait.”

So they waited, but Alec still didn't talk and they saw other troubling signs.

Greacen said, “People would walk into the room and say 'hi Alec' and there was absolutely no response.”

Finally, when Alec was three he was diagnosed with autism.

At that time, Ian was nine months old and the Greacen’s were worried about his future, but doctors told them not to worry he’d be fine.

But Ian wouldn’t be fine.

His mother explains what happened, “Right around 12 to 18 months we realized there was no speech developing and he had some sensory issues.”

When Ian was two he was also diagnosed with autism.

According to nationally known autism expert, Dr. Nancy Minshew, having more than one autistic child in a family isn’t that unusual.

Minshew is Director of the Center for Excellence in Autism Research at the University of Pittsburgh.

Minshew is studying autistic children and their infant siblings.

She said early results from her studies indicate the chance of a family having more than one autistic child is much higher than originally thought.

Many autism experts put that chance at about five percent, but early results from Minshew’s studies show it could be as high as 15 to 18 percent.

She believes autism starts in the first year of life, but the symptoms are missed by most doctors.

Minshew said, “We know looking at birthday video tapes at 12 months of age that it's already off track, so the idea that there is nothing going on in the first year that's abnormal is not true.”

Right now in the Pittsburgh area most children with autism are not diagnosed until they are three or four years old.

She believes if the signs of autism are detected early and autism is diagnosed much earlier, it could mean a more normal life for autistic kids.

Minshew said, “We need to do early intervention to improve outcomes that means starting at two, three at the latest. We can help pediatricians know what to look for and we can begin to see what we can do in the first year of life to head this off, to make it milder.”

The Greacens believe early intervention made a big difference for Ian.

He was diagnosed a year earlier than his brother and began therapy a year earlier.

Ian is now more independent, verbal and social than his older brother.

If parents feel something is just not right with their child, Greacen has this advice, "Trust your gut. It's better to air on the safe side then putting if off and wasting that valuable time.”

Dr. Minchew is expanding her study. Her researchers will follow 150 families who have one autistic child with an infant sibling. She will also follow another 150 families with an infant who do not have autistic children.

The University Of Pittsburgh Center for Excellence in Autism Research is also conducting studies on older children and adults with autism.

If you are interested in taking part in those studies you can get more information by calling 412-246-5485 or emailing autismrecruiter@upmc.edu.