This example shows an interactive family tree built with D3.js, displaying a hierarchical dataset of names and parent-child relationships. The visualization uses the `d3.layout.tree` layout to position nodes and `d3.svg.diagonal` for the curved links between them. Each node is rendered as an SVG circle with a text label, and clicking on a node toggles its children, collapsing or expanding that branch. The nodes and links animate smoothly via transitions, with colors indicating different levels in the hierarchy.