Question: How do i solve the *Parameter child must be non-null* error?  

I'm trying to remove instances (box1, box2, box3, box4) that have `.y <= 56`

The code follows:

```
for (i=1; i<=4; i++)
{
    this["Box" + i].addEventListener(Event.ENTER_FRAME, Move);
}

function Move(e:Event):void
{
    e.target.y -=  6;
    if (e.target.y <= 56)
    {
        removeChild(getChildByName(e.target.name));
        Comment.text = "MISS";
        miss +=  1;
        score +=  0;
    }
}

```

Answer: 
Try

```
$().validate({
    errorPlacement : function(error, element) {
        $('#errorct').append(error)
    }
})

```

demo: [Fiddle](http://jsfiddle.net/arunpjohny/XHDvS/)
Make a div with an id (for example #error) at the top of you form, generate an error message (submit.php), check if field is empty and load the error message into the div #error.

```
<script type="text/javascript">
jQuery('#error', window.parent.document).html( function(){
$(this).text('<?=$errorMessage;?>');
});
</script>

```

edit: Saw this to late...you use the validation lib. ...hope this helps anyway...