code: function( contentItem, keepChild ) {
  		
  		/*
  		 * Get the position of the item that's to be removed within all content items this node contains
  		 */
  		var index = lm.utils.indexOf( contentItem, this.contentItems );
  
  		/*
  		 * Make sure the content item to be removed is actually a child of this item
  		 */
  		if( index === -1 ) {
  			throw new Error( 'Can\'t remove child item. Unknown content item' );
  		}
  
  		/**
  		 * Call ._$destroy on the content item. This also calls ._$destroy on all its children
  		 */
  		if( keepChild !== true ) {
  			this.contentItems[ index ]._$destroy();
  		}
  		
  		/**
  		 * Remove the content item from this nodes array of children
  		 */
  		this.contentItems.splice( index, 1 );
  
  		/**
  		 * Remove the item from the configuration
  		 */
  		this.config.content.splice( index, 1 );
  
  		/**
  		 * If this node still contains other content items, adjust their size
  		 */
  		if( this.contentItems.length > 0 ) {
  			this.callDownwards( 'setSize' );
  
  		/**
  		 * If this was the last content item, remove this node as well
  		 */
  		} else if( !(this instanceof lm.items.Root) ) {
  			this.parent.removeChild( this );
  		}
  	}
docs: Removes a child node (and its children) from the tree
  
  @param   {lm.items.ContentItem} contentItem
  
  @returns {void}