Cavemen

On the Halo 3 level "Sierra 117", you can find a family of cavemen.

To find the family, go past the point where Johnson's Pelican gets shot down. You will see a concrete column with the number 3 on it. When you stay beside the left wall and go as high as you can, you must turn around and you will see the cavemen against the wall. The largest of them is holding a teddy bear.