Linda Strickland "They were best friends. They weren't just brothers. They went everywhere together. Everywhere."

Linda Strickland's teenage sons, Ted and Alex, took the car on their very first road trip and were in a horrible car accident. Ted survived, but Alex and another passenger died. Linda Strickland "I should have said no. But people were telling me 'cut the apron strings.' I cut the apron strings, now my son is dead."

While it's impossible to prevent your child from getting into an accident, Consumer Reports tested small GPS-tracking devices that warn you in advance how your teen is driving.

There's MotoSafety, Mastrack, and MobiCoPilot that cost between 80 and 150 dollars. They are easy to install in the diagnostic port under the dashboard. And you'll pay 15 to 20 dollars per month for driving reports. "So they do things like alert you if your teen is speeding, slamming on the brakes, or really gunning the car."

You can have the alerts sent to you via text or e-mail, or view driving reports on the device's website. You can also see the vehicle's location and the route. All the devices worked well. Liza Barth "Don't think of it as spying on your teen, but coaching them to be a better driver." The least expensive - the 80-dollar MOTOSafety - is enough for simple tracking, and it allows you to set top speeds for highways and secondary roads.

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