diff --git a/CHANGELOG.mkdn b/CHANGELOG.mkdn
index 95ed34a..cb07101 100644
--- a/CHANGELOG.mkdn
+++ b/CHANGELOG.mkdn
@@ -23,6 +23,7 @@ CHANGELOG
 * Rearrange options menu, make tabbed - Kiooeht [evacipatedBox]
 * Rearrange memos window for readability - Kiooeht [evacipatedBox]
 * Give voice to memo users - Kiooeht [evacipatedBox]
+* Theme checking - Kiooeht [evacipatedBox]
 * Bug fixes
     * Logviewer updates - Kiooeht [evacipatedBox]
     * Memo scrollbar thing - Kiooeht [evacipatedBox]
@@ -31,6 +32,7 @@ CHANGELOG
     * Stay in memos on profile switch - Kiooeht [evacipatedBox]
     * Auto rejoin memos on reconnect - Kiooeht [evacipatedBox]
     * De-Op in memos correctly - Kiooeht [evacipatedBox]
+    * Don't blow up if someone's not using Pesterchum in a memo - Kiooeht [evacipatedBox]
 
 ### 3.14.1
 * Pesterchum 3.14 - illuminatedwax [ghostDunk]
diff --git a/memos.py b/memos.py
index fafd13f..0e86a08 100644
--- a/memos.py
+++ b/memos.py
@@ -163,6 +163,8 @@ class TimeTracker(list):
         timed = self.getTime()
         return self.getGrammarTime(timed)
     def getGrammarTime(self, timed):
+        if not timed:
+            timed = timedelta(0)
         mytime = timedelta(0)
         (temporal, pcf, when) = pcfGrammar(timed - mytime)
         if timed == mytime: