{"id":"sibling-pointers-leaf-only","text":"Sibling pointers exist only on leaf nodes (`_serialize_leaf` at line 182); internal nodes have no right-links, making this a B+-tree, not a B-link tree","truth_value":"IN","source":"entries/2026/05/29/topic-sibling-pointer-maintenance.md","source_url":"","source_hash":"","justifications":[],"dependents":[],"metadata":{},"explanation":{"steps":[{"node":"sibling-pointers-leaf-only","truth_value":"IN","reason":"premise"}]}}