diff --git a/src/main/java/org/forkalsrud/album/exif/DirectoryEntry.java b/src/main/java/org/forkalsrud/album/exif/DirectoryEntry.java
index d072af9..6a4b500 100644
--- a/src/main/java/org/forkalsrud/album/exif/DirectoryEntry.java
+++ b/src/main/java/org/forkalsrud/album/exif/DirectoryEntry.java
@@ -108,7 +108,7 @@ public class DirectoryEntry extends Entry {
         return null;
     }
 
-    protected void loadChildren() {
+    protected synchronized void loadChildren() {
 
         if (childrenLoaded) {
             return;