Invoke super.clone() instead of creating a new instance in the clone methods.

src/main/java/org/elasticsearch/index/search/child/ChildrenConstantScoreQuery.java

@@ -51,7 +51,7 @@ import java.util.Set;
 public class ChildrenConstantScoreQuery extends Query {
 
     private final ParentChildIndexFieldData parentChildIndexFieldData;
-    private final Query originalChildQuery;
+    private Query originalChildQuery;
     private final String parentType;
     private final String childType;
     private final Filter parentFilter;
@@ -88,12 +88,10 @@ public class ChildrenConstantScoreQuery extends Query {
 
     @Override
     public Query clone() {
-        ChildrenConstantScoreQuery q = new ChildrenConstantScoreQuery(parentChildIndexFieldData, originalChildQuery.clone(),
-                parentType, childType, parentFilter, shortCircuitParentDocSet, nonNestedDocsFilter);
-        q.setBoost(getBoost());
+        ChildrenConstantScoreQuery q = (ChildrenConstantScoreQuery) super.clone();
+        q.originalChildQuery = originalChildQuery.clone();
         if (q.rewrittenChildQuery != null) {
             q.rewrittenChildQuery = rewrittenChildQuery.clone();
-            q.rewriteIndexReader = rewriteIndexReader;
         }
         return q;
     }

src/main/java/org/elasticsearch/index/search/child/ChildrenQuery.java

@@ -63,7 +63,7 @@ public class ChildrenQuery extends Query {
     private final String childType;
     private final Filter parentFilter;
     private final ScoreType scoreType;
-    private final Query originalChildQuery;
+    private Query originalChildQuery;
     private final int shortCircuitParentDocSet;
     private final Filter nonNestedDocsFilter;
 
@@ -131,12 +131,10 @@ public class ChildrenQuery extends Query {
 
     @Override
     public Query clone() {
-        ChildrenQuery q = new ChildrenQuery(parentChildIndexFieldData, parentType, childType, parentFilter,
-                originalChildQuery, scoreType, shortCircuitParentDocSet, nonNestedDocsFilter);
-        q.setBoost(getBoost());
+        ChildrenQuery q = (ChildrenQuery) super.clone();
+        q.originalChildQuery = originalChildQuery.clone();
         if (q.rewrittenChildQuery != null) {
             q.rewrittenChildQuery = rewrittenChildQuery.clone();
-            q.rewriteIndexReader = rewriteIndexReader;
         }
         return q;
     }

src/main/java/org/elasticsearch/index/search/child/ParentConstantScoreQuery.java

@@ -46,7 +46,7 @@ import java.util.Set;
 public class ParentConstantScoreQuery extends Query {
 
     private final ParentChildIndexFieldData parentChildIndexFieldData;
-    private final Query originalParentQuery;
+    private Query originalParentQuery;
     private final String parentType;
     private final Filter childrenFilter;
 
@@ -77,12 +77,10 @@ public class ParentConstantScoreQuery extends Query {
 
     @Override
     public Query clone() {
-        ParentConstantScoreQuery q = new ParentConstantScoreQuery(parentChildIndexFieldData, originalParentQuery,
-                parentType, childrenFilter);
-        q.setBoost(getBoost());
+        ParentConstantScoreQuery q = (ParentConstantScoreQuery) super.clone();
+        q.originalParentQuery = originalParentQuery.clone();
         if (q.rewrittenParentQuery != null) {
             q.rewrittenParentQuery = rewrittenParentQuery.clone();
-            q.rewriteIndexReader = rewriteIndexReader;
         }
         return q;
     }

src/main/java/org/elasticsearch/index/search/child/ParentQuery.java

@@ -52,7 +52,7 @@ import java.util.Set;
 public class ParentQuery extends Query {
 
     private final ParentChildIndexFieldData parentChildIndexFieldData;
-    private final Query originalParentQuery;
+    private Query originalParentQuery;
     private final String parentType;
     private final Filter childrenFilter;
 
@@ -122,11 +122,10 @@ public class ParentQuery extends Query {
 
     @Override
     public Query clone() {
-        ParentQuery q = new ParentQuery(parentChildIndexFieldData, originalParentQuery, parentType, childrenFilter);
-        q.setBoost(getBoost());
+        ParentQuery q = (ParentQuery) super.clone();
+        q.originalParentQuery = originalParentQuery.clone();
         if (q.rewrittenParentQuery != null) {
             q.rewrittenParentQuery = rewrittenParentQuery.clone();
-            q.rewriteIndexReader = rewriteIndexReader;
         }
         return q;
     }

src/main/java/org/elasticsearch/index/search/child/TopChildrenQuery.java

@@ -69,7 +69,7 @@ public class TopChildrenQuery extends Query {
     private final ScoreType scoreType;
     private final int factor;
     private final int incrementalFactor;
-    private final Query originalChildQuery;
+    private Query originalChildQuery;
     private final Filter nonNestedDocsFilter;
 
     // This field will hold the rewritten form of originalChildQuery, so that we can reuse it
@@ -108,14 +108,10 @@ public class TopChildrenQuery extends Query {
 
     @Override
     public Query clone() {
-        TopChildrenQuery q = new TopChildrenQuery(
-                parentChildIndexFieldData, originalChildQuery.clone(), childType, parentType,
-                scoreType, factor, incrementalFactor, cacheRecycler, nonNestedDocsFilter
-        );
-        q.setBoost(getBoost());
+        TopChildrenQuery q = (TopChildrenQuery) super.clone();
+        q.originalChildQuery = originalChildQuery.clone();
         if (q.rewrittenChildQuery != null) {
             q.rewrittenChildQuery = rewrittenChildQuery.clone();
-            q.rewriteIndexReader = rewriteIndexReader;
         }
         return q;
     }