this could use a lot of work... the head isnt realy symetric, the mouth is crooked, the ears are too high ( they should be on one level with the eyes ), also the cap is kinda small....
i made a quick edit, dont know if it looks anything lilke ur brother but maybe it can help you ^^ :
http://i992.photobucket.com/albums/af45/oooonek/redhead.gif
This is supposed to look like those other same style avatars