title: WordPress Custom Post types parent/child relationship
body: <p>I am building a website for an art gallery using WordPress.
  For some of the content I am using Custom Post types.</p>
  
  <p>I have 4, Artists, Exhibitions, Works Available and Artist News.
  I need the Artist Custom Post type to act as the parent and the other 3 to act as the child then on the front end I need to have a menu on the Artists page like this:</p>
  
  <p>Jo Blo (Artist)</p>
  
  <ul>
  <li>Artist News </li>
  <li>Work Avaliable</li>
  <li>Exhibitions</li>
  </ul>
  
  <p>What I need to do but can't work out how is to set it up so I can choose an Artist as a parent for 1 of the 3 child custom post types.</p>
  
  <p>I know that if I put 'attributes' in the line supports in the functions.php file when I register the custom post type as well as set hierarchical to true it as the parent box but it only allows me to chose another post from that type.</p>
  
  <p>Is it possible to choose a parent for a custom post from another custom post type and if so how do I set that up?</p>
  
  <p>Any help would be greatly appreciated.</p>
  
  <p>Cheers</p>