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diff --git a/‎objectbox-java/src/main/java/io/objectbox/relation/RelationInfo.java‎
Lines changed: 27 additions & 7 deletions b/‎objectbox-java/src/main/java/io/objectbox/relation/RelationInfo.java‎
Lines changed: 27 additions & 7 deletions
diff --git a/‎objectbox-java/src/main/java/io/objectbox/relation/ToMany.java‎
Lines changed: 14 additions & 2 deletions b/‎objectbox-java/src/main/java/io/objectbox/relation/ToMany.java‎
Lines changed: 14 additions & 2 deletions
@@ -26,27 +26,30 @@
 import io.objectbox.internal.ToManyGetter;
 import io.objectbox.internal.ToOneGetter;
 
-@Internal
-@Immutable
 /**
  * Meta info describing a relation including source and target entity.
  */
+@Internal
+@Immutable
 public class RelationInfo<TARGET> implements Serializable {
     private static final long serialVersionUID = 7412962174183812632L;
 
     public final EntityInfo sourceInfo;
     public final EntityInfo<TARGET> targetInfo;
 
-    /** For relations based on a target ID property (null for stand-alone relations). */
+    /** For relations based on a target ID property (null otherwise). */
     public final Property targetIdProperty;
 
+    /** For ToMany relations based on ToMany backlinks (0 otherwise). */
+    public final int targetRelationId;
+
     /** Only set for ToOne relations */
     public final ToOneGetter toOneGetter;
 
     /** Only set for ToMany relations */
     public final ToManyGetter toManyGetter;
 
-    /** For ToMany relations based on backlinks (null for stand-alone relations). */
+    /** For ToMany relations based on ToOne backlinks (null otherwise). */
     public final ToOneGetter backlinkToOneGetter;
 
     /** For stand-alone to-many relations (0 otherwise). */
@@ -61,6 +64,7 @@ public RelationInfo(EntityInfo sourceInfo, EntityInfo<TARGET> targetInfo, Proper
         this.targetInfo = targetInfo;
         this.targetIdProperty = targetIdProperty;
         this.toOneGetter = toOneGetter;
+        this.targetRelationId = 0;
         this.backlinkToOneGetter = null;
         this.toManyGetter = null;
         this.relationId = 0;
@@ -76,22 +80,38 @@ public RelationInfo(EntityInfo sourceInfo, EntityInfo<TARGET> targetInfo, ToMany
         this.targetIdProperty = targetIdProperty;
         this.toManyGetter = toManyGetter;
         this.backlinkToOneGetter = backlinkToOneGetter;
+        this.targetRelationId = 0;
         this.toOneGetter = null;
         this.relationId = 0;
     }
 
     /**
-     * Stand-alone ToMany.
+     * ToMany as a ToMany backlink or stand-alone ToMany.
      */
     public RelationInfo(EntityInfo sourceInfo, EntityInfo<TARGET> targetInfo, ToManyGetter toManyGetter,
-                        int relationId) {
+            int relationId, boolean isBacklink) {
         this.sourceInfo = sourceInfo;
         this.targetInfo = targetInfo;
-        this.relationId = relationId;
         this.toManyGetter = toManyGetter;
         this.targetIdProperty = null;
         this.toOneGetter = null;
         this.backlinkToOneGetter = null;
+        if (isBacklink) {
+            this.relationId = 0;
+            this.targetRelationId = relationId;
+        } else {
+            // stand-alone
+            this.relationId = relationId;
+            this.targetRelationId = 0;
+        }
+    }
+
+    /**
+     * Stand-alone ToMany.
+     */
+    public RelationInfo(EntityInfo sourceInfo, EntityInfo<TARGET> targetInfo, ToManyGetter toManyGetter,
+                        int relationId) {
+        this(sourceInfo, targetInfo, toManyGetter, relationId, false);
     }
 
     @Override
 
@@ -189,8 +189,15 @@ private void ensureEntities() {
                     int sourceEntityId = relationInfo.sourceInfo.getEntityId();
                     newEntities = targetBox.internalGetRelationEntities(sourceEntityId, relationId, id, false);
                 } else {
-                    newEntities = targetBox.internalGetBacklinkEntities(relationInfo.targetInfo.getEntityId(),
-                            relationInfo.targetIdProperty, id);
+                    if (relationInfo.targetIdProperty != null) {
+                        // Backlink from ToOne
+                        newEntities = targetBox.internalGetBacklinkEntities(relationInfo.targetInfo.getEntityId(),
+                                relationInfo.targetIdProperty, id);
+                    } else {
+                        // Backlink from ToMany
+                        newEntities = targetBox.internalGetRelationEntities(relationInfo.targetInfo.getEntityId(),
+                                relationInfo.targetRelationId, id, true);
+                    }
                 }
                 if (comparator != null) {
                     Collections.sort(newEntities, comparator);
@@ -670,6 +677,11 @@ public boolean internalCheckApplyToDbRequired() {
 
     private boolean prepareBacklinkEntitiesForDb() {
         ToOneGetter backlinkToOneGetter = relationInfo.backlinkToOneGetter;
+        if (backlinkToOneGetter == null) {
+            // backlink from ToMany, do not apply changes to db
+            return false;
+        }
+
         long entityId = relationInfo.sourceInfo.getIdGetter().getId(entity);
         if (entityId == 0) {
             throw new IllegalStateException("Source entity has no ID (should have been put before)");