diff --git a/doc/src/sgml/ref/update.sgml b/doc/src/sgml/ref/update.sgml
index 3ba13010e7..3a0285df79 100644
--- a/doc/src/sgml/ref/update.sgml
+++ b/doc/src/sgml/ref/update.sgml
@@ -319,9 +319,9 @@ UPDATE <replaceable class="parameter">count</replaceable>
 
   <para>
    An attempt of moving a row from one partition to another will fail if a
-   foreign key is found to directly reference a non-root partitioned table
-   in the partition tree, unless that table is also directly mentioned
-   in the <command>UPDATE</command>query.
+   foreign key is found to directly reference an ancestor of the source
+   partition that is not the same as the ancestor that's mentioned in the
+   <command>UPDATE</command> query.
   </para>
  </refsect1>
 
diff --git a/src/backend/commands/trigger.c b/src/backend/commands/trigger.c
index 0adecdea22..5fa395fcc2 100644
--- a/src/backend/commands/trigger.c
+++ b/src/backend/commands/trigger.c
@@ -3542,7 +3542,7 @@ typedef SetConstraintStateData *SetConstraintState;
  * Per-trigger-event data
  *
  * The actual per-event data, AfterTriggerEventData, includes DONE/IN_PROGRESS
- * status bits, up to two tuple CTIDs, and optionally two OIDs of partitions
+ * status bits, up to two tuple CTIDs, and optionally two OIDs of partitions.
  * Each event record also has an associated AfterTriggerSharedData that is
  * shared across all instances of similar events within a "chunk".
  *
@@ -3555,10 +3555,10 @@ typedef SetConstraintStateData *SetConstraintState;
  * tuple(s).  This permits storing tuples once regardless of the number of
  * row-level triggers on a foreign table.
  *
- * When updates move tuples in partitioned tables to different partitions,
+ * When updates of a partitioned table causes rows to move between partitions,
  * the OIDs of both partitions are stored too, so that the tuples can be
  * fetched; such entries are marked AFTER_TRIGGER_CP_UPDATE (for "cross-
- * partition").
+ * partition update").
  *
  * Note that we need triggers on foreign tables to be fired in exactly the
  * order they were queued, so that the tuples come out of the tuplestore in
diff --git a/src/backend/executor/nodeModifyTable.c b/src/backend/executor/nodeModifyTable.c
index de46315405..c822b5b744 100644
--- a/src/backend/executor/nodeModifyTable.c
+++ b/src/backend/executor/nodeModifyTable.c
@@ -1981,7 +1981,7 @@ ExecCrossPartitionUpdateForeignKey(ModifyTableContext *context,
 		TriggerDesc *trigdesc = rInfo->ri_TrigDesc;
 		bool		has_noncloned_fkey = false;
 
-		/* Ignore the root ancestor, because ...?? */
+		/* Root ancestor's triggers will be processed. */
 		if (rInfo == rootRelInfo)
 			continue;