Chevrolet 2003 Cavalier Owner's Manual page 40

Never do this.
Here a child is sitting in a seat that has a
lap-shoulder belt, but the shoulder part is
behind the child. If the child wears the belt
inthis way, in a crash the child might slide
under the belt. The belt's force would then be
applied right on the child's abdomen. That
could cause serious or fatal injuries.
Wherever the child sits, the lap portion of the beit
should be worn low and snug on the hips, just touching
the child's thighs. This applies belt force to the child's
pelvic bones in a crash.
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