It is a Phyllurus platurus. The common name varies. Sometimes it is called "Southern Leaf-tailed Gecko" and other times "Broad-tailed Gecko". They are great looking geckos -- your brother is lucky to have one in the house.
Thanks mate Yeah, thats what I told him. He reckons it's quite big, bout 15 - 20cm. I told him it was a leaf tail, but wanted the scientific name, so cheers for that
He also said that he touched it on the back, and it made a really wierd noise - freaked him out - wasn't expecting it