Chevrolet HHR 2011 Owner's Manual page 67

Also see Rear Safety Belt Comfort Guides under
Lap-Shoulder Belt on page 2 28.
According to accident statistics, children and infants are
safer when properly restrained in a child restraint
system or infant restraint system secured in a rear
seating position.
In a crash, children who are not buckled up can strike
other people who are buckled up, or can be thrown out
of the vehicle. Older children need to use safety belts
properly.
WARNING:
Never do this.
Never allow two children to wear the same safety
belt. The safety belt can not properly spread the
impact forces. In a crash, the two children can be
crushed together and seriously injured. A safety
belt must be used by only one person at a time.
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