Buick 2006 Rendezvous Owner's Manual page 68

If you are using a top tether equipped child restraint
in the second row center bench seat and need to
temporarily transport a flat tire for repair, move the
child restraint to a rear seat outboard position.
See Securing a Child Restraint in a Rear Outside Seat
Position on page 1-65 for more information including
important safety information.
Third Row
If the vehicle has a third row, there is a top tether
anchor for the third row passenger's side position.
Locate the anchor symbol on the flap of carpet behind
the seat. Lift up the carpet to access the anchor.
1-62
Do not secure a child restraint in the right front
passenger's position or in the third row driver side
position, if equipped, if a national or local law requires
that the top tether be attached, or if the instructions that
come with the child restraint say that the top tether
must be attached. There is no place to attach the top
tether in this position.
Accident statistics show that children are safer if they
are restrained in the rear rather than the front seat.
See Where to Put the Restraint on page 1-54 for
additional information.