Cadillac GMC Yukon Denali 2005 Owner's Manual page 55

Q:
What if a child is wearing a lap-shoulder belt,
but the child is so small that the shoulder belt
is very close to the child's face or neck?
A:
If the child is sitting in a rear seat outside position,
move the child toward the center of the vehicle. If
the child is sitting in the center position, move
the child toward the safety belt buckle. In either
case, be sure that the shoulder belt still is on
the child's shoulder, so that in a crash the child's
upper body would have the restraint that belts
provide. See Rear Safety Belt Comfort Guides for
Children and Small Adults on page 1-44.
If the child is so small that the shoulder belt is still
very close to the child's face or neck, you might
want to place the child in a seat that has a lap belt,
if your vehicle has one.
CAUTION:
{
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.
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