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
in
this 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 belt
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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