GREENVILLE — A national advocate for homelessness told a crowd at Thiel College on Tuesday their idea of the typical homeless person is probably wrong.

Most of the crowd at the Greenville college raised their hands when Diane Nilan asked if they thought a homeless person is often a grizzled man with drugs or alcohol living under a bridge.

Even though the United States is one of the richest countries, families with children make up a good portion of the homeless population, she said.

“It absolutely tends to blow people’s minds,” Ms. Nilan said.

Ms. Nilan is the founder of HEAR US Inc., an Illinois-based organization that advocates for homeless children and teens. She sold her home and most of her belongings in 2005 to travel the country in a recreational vehicle, gathering stories from those people.

Her documentary, “My Own Four Walls,” features those interviews, mainly from the back roads and non-urban areas of the country, not big cities. Ms. Nilan is on her fifth tour of the country and continues to meet youth willing to share their stories.

“I am truly honored every time I see this film,” she said before showing a 20-minute clip.

Children of all ages spoke of how they became homeless because of hurricanes, fires, abandonment or when parents got into trouble with the law.

“I was so mad I didn’t even care he was in jail,” a boy named Brad from Arkansas said of when his father got arrested for having a meth lab at their home.

Some of the children said they didn’t like living in homeless shelters because they’re crowded, full of strangers and have a lot of rules.

Others spoke of school as a safe haven where their friends are, a situation made difficult if their family has to move.

“School is everything to me,” Nathan of Pennsylvania said.

One little girl said she feels bad and sad for having to tell her friends they can’t come to her home because she doesn’t have a permanent one.

“I feel bad about it. It breaks my heart,” she said.

The children remained hopeful, saying they want to go to college, become lawyers, president of the United States, anything to be able to support their families.

“All of this was unrehearsed,” Ms. Nilan said after the clip ended.

There are about 1.5 to 3 million homeless youth in the country. Some of their families live doubled up with others, at campgrounds or bounce from hotel to hotel or shelter to shelter, she said.

Ms. Nilan was shocked to learn many communities don’t even have shelters. Some of the country’s lawmakers don’t believe homelessness is as widespread as the statistics show, she said.

“No wonder we’re in the mess that we’re in,” she said.

She’s working on a new project to talk to U.S. Congress people about the homelessness problems in the areas they represent. She urged the crowd to do the same after hearing from local housing representatives about homelessness in Mercer County.

In 2008, 476 families were homeless and that number is 690 so far in 2009, said Natalie Higbee of the Prince of Peace Center, Farrell. She’s also involved with the Mercer County Housing Coalition.

Various organizations try to help as many families as they can, but there aren’t enough resources to go around, she said.

“Do something to make the world a better place,” Ms. Nilan said.

Locally, the Mercer County Commissioners on Thursday will declare November Homeless Awareness Month, Ms. Higbee said. The housing coalition is hosting a homeless awareness walk starting at 3 p.m. Nov. 1 at Joshua’s Haven City Mission, 205 Bank Place, Sharon.

The Kindness Kampaign in Greenville is also hosting a walk at 3 p.m. Nov. 1.

For more information about helping the homeless in Mercer County, call the Prince of Peace at 724-346-5777; Mercer County Behavioral Health Commission at 724-662-1550; or Good Shepherd Center at 724-588-2210.

To register for the Sharon walk, call Ms. Higbee at Prince of Peace and for the Greenville walk, call John O’Malley at 724-813-4884.

Visit www.hearus.us for more information about Ms. Nilan’s work.