GMC 1998 Jimmy Owner's Manual page 56

A
CAUTION:
Never hold a baby in your arms while riding in a
vehicle. A baby doesn't weigh much
--
until a
crash. During a crash a baby will become so
heavy you can't hold it. For example, in a crash
CAUTION: (Continued)
at only 25 mph (40 kmk), a 12-lb. (5.5 kg) baby
will suddenly become
a 240-lb. (110 kg) force
on
your arms. The baby would be almost impossible
to hold.
Secure the baby in an infant restraint.
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