I defined a LaTeX environment tikzfamilytree that facilitates drawing a family tree with TikZ. Here is a small working example (in XeLaTeX). The code provides further documentation. Note that the way people’s names and partnerships are displayed is controlled by commands that fall outside the environment definition. For instance, in my example I use colored Webdings symbols to indicate gender.
Using the uncovering method I described earlier, you can also draw a family tree in a Beamer document and uncover it piecewise. This requires no alterations to the tikzfamilytree environment, but just some customization of the aforementioned displaying commands. The same example looks like this in Beamer (XeLaTeX source):