name = 'father/2'
slug = 'the father-child relation'

description = '''\
<p><code>father(X, Y)</code>: <code>X</code> is the father of <code>Y</code>.</p>
<pre>
?- father(thomas, william).
  true.
?- father(aleksander, X).
  X = luana ;
  X = daniela.
</pre>'''

hint = {}