diff --git a/.ci/pitest-suppressions/pitest-whitespace-suppressions.xml b/.ci/pitest-suppressions/pitest-whitespace-suppressions.xml
index 963bf9202e3..429915a0b00 100644
--- a/.ci/pitest-suppressions/pitest-whitespace-suppressions.xml
+++ b/.ci/pitest-suppressions/pitest-whitespace-suppressions.xml
@@ -116,22 +116,4 @@
     <description>replaced call to com/puppycrawl/tools/checkstyle/utils/CodePointUtil::trim with argument</description>
     <lineContent>final int[] substringAfterToken = CodePointUtil.trim(</lineContent>
   </mutation>
-
-  <mutation unstable="false">
-    <sourceFile>SingleSpaceSeparatorCheck.java</sourceFile>
-    <mutatedClass>com.puppycrawl.tools.checkstyle.checks.whitespace.SingleSpaceSeparatorCheck</mutatedClass>
-    <mutatedMethod>visitEachToken</mutatedMethod>
-    <mutator>org.pitest.mutationtest.engine.gregor.mutators.NonVoidMethodCallMutator</mutator>
-    <description>removed call to com/puppycrawl/tools/checkstyle/api/DetailAST::getParent</description>
-    <lineContent>final DetailAST parent = node.getParent();</lineContent>
-  </mutation>
-
-  <mutation unstable="false">
-    <sourceFile>SingleSpaceSeparatorCheck.java</sourceFile>
-    <mutatedClass>com.puppycrawl.tools.checkstyle.checks.whitespace.SingleSpaceSeparatorCheck</mutatedClass>
-    <mutatedMethod>visitEachToken</mutatedMethod>
-    <mutator>org.pitest.mutationtest.engine.gregor.mutators.experimental.NakedReceiverMutator</mutator>
-    <description>replaced call to com/puppycrawl/tools/checkstyle/api/DetailAST::getParent with receiver</description>
-    <lineContent>final DetailAST parent = node.getParent();</lineContent>
-  </mutation>
 </suppressedMutations>
diff --git a/src/main/java/com/puppycrawl/tools/checkstyle/checks/whitespace/SingleSpaceSeparatorCheck.java b/src/main/java/com/puppycrawl/tools/checkstyle/checks/whitespace/SingleSpaceSeparatorCheck.java
index 7dae2bf80f3..fade4a68149 100644
--- a/src/main/java/com/puppycrawl/tools/checkstyle/checks/whitespace/SingleSpaceSeparatorCheck.java
+++ b/src/main/java/com/puppycrawl/tools/checkstyle/checks/whitespace/SingleSpaceSeparatorCheck.java
@@ -179,7 +179,6 @@ public void beginTree(DetailAST rootAST) {
      */
     private void visitEachToken(DetailAST node) {
         DetailAST currentNode = node;
-        final DetailAST parent = node.getParent();
 
         do {
             final int columnNo = currentNode.getColumnNo() - 1;
@@ -199,7 +198,7 @@ private void visitEachToken(DetailAST node) {
                 currentNode = currentNode.getFirstChild();
             }
             else {
-                while (currentNode.getNextSibling() == null && currentNode.getParent() != parent) {
+                while (currentNode.getNextSibling() == null && currentNode.getParent() != null) {
                     currentNode = currentNode.getParent();
                 }
                 currentNode = currentNode.getNextSibling();