diff --git a/src/node/handlers/mmp.rs b/src/node/handlers/mmp.rs
index 7c2e079..328f62e 100644
--- a/src/node/handlers/mmp.rs
+++ b/src/node/handlers/mmp.rs
@@ -452,11 +452,18 @@ impl Node {
         let mut dead_peers: Vec<NodeAddr> = Vec::new();
 
         for (node_addr, peer) in self.peers.iter() {
-            // Check liveness via MMP receiver last_recv_time
-            if let Some(mmp) = peer.mmp()
-                && let Some(last_recv) = mmp.receiver.last_recv_time()
-                && now.duration_since(last_recv) >= dead_timeout
-            {
+            // Check liveness via MMP receiver last_recv_time.
+            // Fall back to session_start for peers that never sent data.
+            let is_dead = if let Some(mmp) = peer.mmp() {
+                let reference_time = mmp
+                    .receiver
+                    .last_recv_time()
+                    .unwrap_or(peer.session_start());
+                now.duration_since(reference_time) >= dead_timeout
+            } else {
+                false
+            };
+            if is_dead {
                 dead_peers.push(*node_addr);
                 continue;
             }
diff --git a/src/peer/active.rs b/src/peer/active.rs
index 8da5024..f6d5997 100644
--- a/src/peer/active.rs
+++ b/src/peer/active.rs
@@ -544,6 +544,11 @@ impl ActivePeer {
         self.session_start.elapsed().as_millis() as u32
     }
 
+    /// When this peer's session started (for link-dead fallback timing).
+    pub fn session_start(&self) -> Instant {
+        self.session_start
+    }
+
     // === Heartbeat ===
 
     /// When we last sent a heartbeat to this peer.