This interactive family tree visualizes a multi-generational genealogy dataset. The graph displays hierarchical relationships between individuals, with each node representing a person and connecting lines showing parent-child links. Users can click on nodes to expand or collapse their subtree, dynamically revealing or hiding descendants. The visualization uses the D3.js layout tree algorithm to position nodes and SVG paths for connections, with CSS-driven animations smoothly transitioning nodes between states. The code leverages D3's select, transition, and append APIs to manage the animated updates triggered by user interactions.