Here is a richer example of what GRAPHVIZ can do.
Note the use of colours, and the "trick" for avoiding lines inside the box containing the names of the children. The blue coloured forms are those of our direct ancestors.
The PSTRICKS command: \rotateleft is used to turn the graph.
The following are the macro files and the forms that I used. \hsize, \vsize, \hoffset and
\voffset should be modified to fit your needs. You may also find some of the shell files given in the computer section useful.