return isInArray(activity1.id, activity1.parentActivity.item, 'id'); 
return isInArray(activity2.id, activity1.parentActivity.item, 'id'); 
	function isSibling(activity1, activity2) 	{		return isInArray(activity1.id, activity1.parentActivity.item, 'id');	}
6251	/local1/tlutelli/issta_data/temp/all_js/javascript/2007_temp/2007/6251/02b1b8d25ec3768079b8e0a010d07cf7e2e12427/sequencing.js/clean/Modules/Scorm2004/scripts/sequencing.js