diff --git a/packages/SwingSet/src/kernel/slogger.js b/packages/SwingSet/src/kernel/slogger.js
index caf9671c86a..b88ac1e8528 100644
--- a/packages/SwingSet/src/kernel/slogger.js
+++ b/packages/SwingSet/src/kernel/slogger.js
@@ -138,6 +138,10 @@ export function makeSlogger(slogCallbacks, writeObj) {
       const vc = {};
       for (const level of ['debug', 'log', 'info', 'warn', 'error']) {
         vc[level] = (sourceTag, ...args) => {
+          if (replay) {
+            // Don't duplicate stale console output.
+            return;
+          }
           sourcedConsole[level](sourceTag, ...args);
           const when = { state, crankNum, vatID, deliveryNum };
           const source = sourceTag === 'ls' ? 'liveslots' : sourceTag;
diff --git a/packages/cosmic-swingset/src/launch-chain.js b/packages/cosmic-swingset/src/launch-chain.js
index c8468a87093..33c13e848f2 100644
--- a/packages/cosmic-swingset/src/launch-chain.js
+++ b/packages/cosmic-swingset/src/launch-chain.js
@@ -1076,6 +1076,8 @@ export async function launch({
     controller.writeSlogObject(obj);
   }
 
+  console.info('Launched SwingSet kernel');
+
   return {
     blockingSend,
     shutdown,