This example visualizes a family tree as a collapsible hierarchical diagram. It shows three generations of the Reddy family, with each node representing a person and orange curved links connecting parent-child relationships. The tree layout uses D3.js version 3 to position nodes, while SVG circles and text labels render each individual. Users can click any node to expand or collapse its children, with smooth 750-millisecond transitions animating the layout changes. Node colors and text styling are controlled via inline CSS and per-node color properties.