diff --git a/org.hl7.fhir.r5/src/main/java/org/hl7/fhir/r5/elementmodel/Element.java b/org.hl7.fhir.r5/src/main/java/org/hl7/fhir/r5/elementmodel/Element.java
index 0b0d8c5e6..05b5b6ca2 100644
--- a/org.hl7.fhir.r5/src/main/java/org/hl7/fhir/r5/elementmodel/Element.java
+++ b/org.hl7.fhir.r5/src/main/java/org/hl7/fhir/r5/elementmodel/Element.java
@@ -360,9 +360,12 @@ public class Element extends Base {
     if (childMap == null) {
       childMap = new HashMap<>();
       for (Element child : children) {
-        String n = child.getName();
-        if (n.endsWith("[x]")) {
+        String n;
+        if (child.getProperty().getName().endsWith("[x]")) {
+          n = child.getProperty().getName();
           n = n.substring(0, n.length()-3);
+        } else {
+          n = child.getName();
         }
         List<Element> l = childMap.get(n);
         if (l == null) {