This example visualizes a family tree using D3.js v5 within a React framework. It shows hierarchical relationships among named individuals, with nodes colored by depth level: red for the root, blue for the first generation, and green for deeper descendants. The code uses `d3.stratify` to convert flat parent-child data into a hierarchy and `d3.tree` to compute node positions. Links are drawn as cubic bezier curves, and the SVG output includes labeled text for each family member.