When Seth Van Nostrand, 5, goes to bed at night, many times he takes his markers and pencils with him.

“Drawing and coloring — he loves it. It’s one of his favorite things to do,” said his mother, Misty Van Nostrand.

The habit of falling asleep with the art supplies around him can make a mess of the sheets, she said. But it’s something she and her husband, Corey, are willing to deal with if it makes Seth happy.

About two years ago, Seth was diagnosed with Hunter syndrome, a type of Mucopolysaccharidoses disorder — or MPS. It’s a rare degenerative genetic disease that strikes about one in 150,000 children. Today is MPS Awareness Day.

“When he’s at his worst, he pretty much can’t get out of the house. When he’s at his best, he pretty much doesn’t look sick,” Corey Van Nostrand said of Seth. “So, it’s hard for a lot of people to understand what it means.”

Before he was diagnosed, Misty and Corey Van Nostrand said they would take Seth to the emergency room.

Finding out he had Hunter syndrome was like a double-edged sword, Corey said.

“We were relieved to know what it was,” he said. “It allows us to know what he needs. But on the other hand, there’s a fear and an anxiety about the future because you know what it can bring.”

Hunter syndrome can affect every system in the body and cause mental retardation, hearing problems and asthma. People with MPS have problems with their hearts and bones, too. Most who have it don’t live past age 15, and there is no cure, said Joseph Muenzer, an associate professor of pediatrics and genetics at the University of North Carolina in Chapel Hill. Muenzer treats children with Hunter syndrome, including Seth.

Seth Van Nostrand, 5, colors before bedtime as his mother, Misty, helps out Wednesday. Seth suffers from a rare disease known as Hunter syndrome or MPS. It affects one in every 150,000 children.

Hunter syndrome is named for Charles Hunter, a professor of medicine in Canada. People with Hunter syndrome lack an enzyme that helps break down cells.

“It’s like if you recycle and once a week you take your recycled goods to the garage,” Muenzer said. “But rather than taking them to the curb or a center, you let everything build up in the garage. And it gets to the point where your garage no longer can function. That’s what happens with MPS. More and more old cells are in storage and that makes some things less functional.”

The diagnosis forever altered the life of the Van Nostrand family.

“We never expected any of this,” Corey Van Nostrand said. “The life we planned was over, and we started a new one.”

Misty Van Nostrand said Seth seems pretty normal now. But the family knows in the future he will stop talking and his cognitive skills will decline drastically and quickly.

6News video: Family wants to raise awareness about rare disease (02-24-05)

“Looking at him right now, it’s difficult to deal with that,” she said. “But I know from talking with other parents that it will happen and that, when it does, it will be quick.”

Seth’s disease also has meant several appointments a month with doctors, and it caused the family to move from a multi-level home to a large mobile home with one floor.

Corey and Misty Van Nostrand said one of the reasons they chose their home is because there’s a bathroom big enough for a wheelchair — which Seth will need someday. The one-level home also has allowed Seth to move around easily and keep up with his brothers — 10-year-old Darian and 22-month-old Kent — while playing.

“This really has given us more of an appreciation of what we have with our kids,” Misty Van Nostrand said. “We try to live every day showing them and telling them that we love them. We want to make sure our time with them is good and that they can grow up to be responsible and caring adults.”

“You just have to love your kids,” Corey Van Nostrand said.