CHEHALIS, Wash. (AP) - A quick-thinking 9-year-old boy grabbed the wheel of a tractor-trailer rig when his father fell unconscious, called for help and, with the help of a good Samaritan, helped bring the big truck safely to a halt.

“I'm just glad he was with me to keep anyone else from being hurt,” Matt T. Lovo, 32, said of his son, Matthew R. Lovo. “I couldn't be more proud.”

The father and son from Chehalis were hauling two trailers loaded with lumber out of Tillamook on Tuesday, when the elder Lovo fell unconscious.

Young Matthew, who rides with his dad a few times a week during the summer, said he always watches closely when his father operates the 1999 Freightliner.

The boy climbed into the driver's seat and began steering the truck, which had traveled into oncoming lanes of traffic and grazed a power pole, said St. Helens Police Chief Steven Salle.

The child managed to steer the truck back into the correct lanes and used the C.B. radio to ask for help. Someone heard his plea and told him to turn off the ignition key, which he did.

While all that was happening, the big rig passed St. Helens resident Christopher A. Howard, who was driving south into St. Helens and noticed a child at the wheel.

According to Salle, Howard saw the slow-moving big truck “approaching in his lane of travel ... then gradually moving back into the northbound lanes.”

Howard braked to a stop and chased the truck on foot. He soon caught the vehicle, jumped aboard, opened the driver's door and applied the brakes, stopping the truck on U.S. Highway 30.

The Lovo truck had been driving in a 25-mph-zone when Matt Lovo lost consciousness.

“Ten more miles, and we would have been going 60,” the father said.

“The next thing I remember, paramedics were asking me questions on the side of the road,” the elder Lovo said.

Young Matthew said he planned to keep watching his father and learning.

“I was really scared,” he added.