diff --git a/src/components/BlueprintViewer.vue b/src/components/BlueprintViewer.vue
index 6a9edf6..42d9488 100644
--- a/src/components/BlueprintViewer.vue
+++ b/src/components/BlueprintViewer.vue
@@ -1,12 +1,15 @@
 <script setup lang="ts">
 import { computed, ref, watch, type Component } from "vue"
 import type { Blueprint } from "@/data/blueprint"
+import { slugForName } from "@/data/blueprints"
 import FunctionReadout from "@/components/FunctionReadout.vue"
 import CompositionMap from "@/components/CompositionMap.vue"
 import StateMachine from "@/components/StateMachine.vue"
 
 const props = defineProps<{ blueprint: Blueprint; specimen: Component }>()
 
+const extendsSlug = computed(() => slugForName(props.blueprint.extendsName))
+
 const activeId = ref("full")
 // reset to the overview whenever we switch blueprints
 watch(
@@ -47,7 +50,12 @@ const funcCount = computed(() => props.blueprint.functions.length)
       </div>
       <div class="tb-cell">
         <div class="tb-k">Extends</div>
-        <div class="tb-v">{{ blueprint.extendsName ?? "—" }}</div>
+        <div class="tb-v">
+          <RouterLink v-if="extendsSlug" :to="`/b/${extendsSlug}`" class="xlink">{{
+            blueprint.extendsName
+          }}</RouterLink>
+          <template v-else>{{ blueprint.extendsName ?? "—" }}</template>
+        </div>
       </div>
       <div class="tb-cell">
         <div class="tb-k">Role</div>
@@ -168,6 +176,23 @@ const funcCount = computed(() => props.blueprint.functions.length)
       </div>
     </template>
 
+    <!-- COMPANION 3: related blueprints -->
+    <template v-if="blueprint.related?.length">
+      <h2 class="section">Related blueprints</h2>
+      <div class="related">
+        <template v-for="r in blueprint.related" :key="r.name">
+          <RouterLink v-if="slugForName(r.name)" :to="`/b/${slugForName(r.name)}`" class="rel link">
+            <span class="rel-name">{{ r.name }} <span class="rel-arrow">▸</span></span>
+            <span class="rel-rel">{{ r.relation }}</span>
+          </RouterLink>
+          <div v-else class="rel">
+            <span class="rel-name">{{ r.name }}</span>
+            <span class="rel-rel">{{ r.relation }}</span>
+          </div>
+        </template>
+      </div>
+    </template>
+
     <footer class="credit">
       <div>
         <span class="ck">SOURCE</span> blueprint-ontology / blueprints / {{ blueprint.slug }} ·
@@ -456,6 +481,54 @@ code {
   color: #7ea6cd;
 }
 
+/* cross-links */
+.xlink {
+  color: var(--color-secondary);
+  text-decoration: none;
+  border-bottom: 1px dashed color-mix(in srgb, var(--color-secondary) 50%, transparent);
+}
+.xlink:hover {
+  border-bottom-style: solid;
+}
+.related {
+  display: grid;
+  grid-template-columns: repeat(auto-fill, minmax(220px, 1fr));
+  gap: 8px;
+}
+.rel {
+  display: flex;
+  flex-direction: column;
+  gap: 2px;
+  border: 1px solid rgba(200, 226, 255, 0.14);
+  padding: 8px 12px;
+  text-decoration: none;
+}
+.rel.link {
+  border-color: rgba(200, 226, 255, 0.3);
+  cursor: pointer;
+  transition: all 0.12s;
+}
+.rel.link:hover {
+  border-color: var(--color-secondary);
+  background: var(--color-base-200);
+}
+.rel-name {
+  font-size: 13px;
+  color: #7ea6cd;
+}
+.rel.link .rel-name {
+  color: var(--color-secondary);
+}
+.rel-arrow {
+  font-size: 10px;
+}
+.rel-rel {
+  font-size: 10px;
+  letter-spacing: 0.1em;
+  text-transform: uppercase;
+  color: #4f7099;
+}
+
 .credit {
   margin-top: 34px;
   padding-top: 14px;
diff --git a/src/data/rememberMeBlueprint.ts b/src/data/rememberMeBlueprint.ts
index 666b66d..713a47f 100644
--- a/src/data/rememberMeBlueprint.ts
+++ b/src/data/rememberMeBlueprint.ts
@@ -302,4 +302,11 @@ export const rememberMe: Blueprint = {
   },
 
   stateMachine: REMEMBER_ME_MACHINE,
+
+  related: [
+    { name: "PasswordAuth", relation: "host · requires" },
+    { name: "StatelessSession", relation: "sibling capability" },
+    { name: "MFA", relation: "sibling capability" },
+    { name: "Captcha", relation: "sibling capability" },
+  ],
 }