I need to add a block on magento default checkout page i.e in cart.phtml file. So first step I did is, I added a block of code in checkout.xml file in the section
<reference name="content">
<block type="checkout/cart" name="checkout.cart"> .....
Here is my code
<block type="bestseller/bestseller" name="bestseller" template="bestseller/bestseller.phtml"/>
and then in second step i just called its child html section as
<div style="width:220px; float:right;"><?php echo $this->getChildHtml('bestseller');?> </div>
But the problem is when I came to see its frontend I seen this bestseller block is appearing two times on the same checkout page. I don't know what m doing wrong. !!pLease someone help me !