function random_img(){
var myimages=new Array();
myimages[1]="family1.gif";
myimages[2]="family2.gif";
myimages[3]="family3.gif";
myimages[4]="family4.gif";

var ry=Math.floor(Math.random()*myimages.length);
if (ry==0){ ry=1; }
document.write('<img src="img/thumbs/'+myimages[ry]+'" style="width:170px; height:85px; border: 1px solid #fff;" alt="Family" />')
}

random_img();