Load the entire comment by cid.
$cid: The identifying comment id.
$reset: Whether to reset the internal static entity cache. Note that the static cache is disabled in comment_entity_info() by default.
The comment object.
function comment_load($cid, $reset = FALSE) {
  $comment = comment_load_multiple(array(
    $cid,
  ), array(), $reset);
  return $comment ? $comment[$cid] : FALSE;
}