Jeep Grand Cherokee Owner's Manual page 87

THINGS TO KNOW BEFORE STARTING YOUR VEHICLE 85
2
Latch Anchorages Pulling Down The Carpet Floor
Panel To Access Top Tether Strap
In addition, there are top tether strap anchorages behind
each rear seating position located on the back of the seat.
To access the top tether strap anchorages behind the rear
seat, pull the carpeted floor panel away from the seat
back, this will expose the top tether strap anchorages.