Print the current source node of the comment
The node id for the comment is stored in:

$comment-&gt;nid


e.g, in the template, to print out the node, you could:

if (isset($comment-&gt;nid)) {
  print render(node_view(node_load($comment-&gt;nid)));
}


You could also add it as a template variable in preprocess function. 

See node_view for more options