title: Family tree layout with Dot/GraphViz
body: <p>I am trying to draw a family tree with Dot and GraphViz.</p>
  
  <p>This is what I currently have: </p>
  
  <pre><code># just graph set-up
  digraph simpsons {
  ratio = "auto"
  mincross = 2.0
  
  # draw some nodes
  "Abraham"   [shape=box, regular=1, color="blue"] ;
  "Mona"      [shape=box, regular=1, color="pink"] ;
  "Clancy"    [shape=box, regular=1, color="blue"] ;
  "Jackeline" [shape=box, regular=1, color="pink"] ;
  "Herb"      [shape=box, regular=1, color="blue"] ;
  "Homer"     [shape=box, regular=1, color="blue"] ;
  "Marge"     [shape=box, regular=1, color="pink"] ;
  "Patty"     [shape=box, regular=1, color="pink"] ;
  "Selma"     [shape=box, regular=1, color="pink"] ;
  "Bart"      [shape=box, regular=1, color="blue"] ;
  "Lisa"      [shape=box, regular=1, color="pink"] ;
  "Maggie"    [shape=box, regular=1, color="pink"] ;
  "Ling"      [shape=box, regular=1, color="blue"] ;
  # creating tiny nodes w/ no label, no color
  "ParentsHomer" [shape=diamond,style=filled,label="",height=.1,width=.1] ;
  "ParentsMarge" [shape=diamond,style=filled,label="",height=.1,width=.1] ;
  "ParentsBart"  [shape=diamond,style=filled,label="",height=.1,width=.1] ;
  
  # draw the edges
  "Abraham"      -&gt; "ParentsHomer" [dir=none, weight=1] ;
  "Mona"         -&gt; "ParentsHomer" [dir=none, weight=1] ;
  "ParentsHomer" -&gt; "Homer"        [dir=none, weight=2] ;
  "ParentsHomer" -&gt; "Herb"         [dir=none, weight=2] ;
  "Clancy"       -&gt; "ParentsMarge" [dir=none, weight=1] ;
  "Jackeline"    -&gt; "ParentsMarge" [dir=none, weight=1] ;
  "ParentsMarge" -&gt; "Marge"        [dir=none, weight=2] ;
  "ParentsMarge" -&gt; "Patty"        [dir=none, weight=2] ;
  "ParentsMarge" -&gt; "Selma"        [dir=none, weight=2] ;
  "Homer"        -&gt; "ParentsBart"  [dir=none, weight=1] ;
  "Marge"        -&gt; "ParentsBart"  [dir=none, weight=1] ;
  "ParentsBart"  -&gt; "Bart"         [dir=none, weight=2] ;
  "ParentsBart"  -&gt; "Lisa"         [dir=none, weight=2] ;
  "ParentsBart"  -&gt; "Maggie"       [dir=none, weight=2] ;
  "Selma"        -&gt; "Ling"         [dir=none, weight=2] ;
  }
  </code></pre>
  
  <p>If I run this through dot (<code>dot simpsons.dot -Tsvg &gt; simpsons.svg</code>),
  I get the following layout: 
  <img src="https://i.imgur.com/gxSzS.png" alt="Original, made by dot/graphviz"></p>
  
  <p>However, I'd like the edges to be more "family tree"-like: a T-junction between two married persons with the vertical line of the T again branching in an upside-down T-junction with small subdivisions for each of the children, like this mock-up, done in KolourPaint:</p>
  
  <p><img src="https://i.imgur.com/H7jAX.png" alt="what I would like to achieve"></p>
  
  <p>What is the dot syntax that I have to use to achieve this?</p>