Your question is DOM Parent-Child Relationships. Take a moment with it on the right.
Talk me through your thinking if you like. When you're confident, submit your answer and I'll grade it like a real screen (7/10 or better passes).
Describe the relationship between parent and child nodes in a DOM tree.
Explain how nodes are connected, how traversal works in both directions, and how adding, removing, or moving a node affects its relationship to the tree. Use standard browser DOM APIs and a small HTML example to make the explanation concrete.