excluding a code doesn't exclude it's children.

src/Hl7.Fhir.Shims.Base/Specification/Terminology/ValueSetExpander.cs

@@ -322,8 +322,12 @@ public static ValueSet.ContainsComponent Add(this List<ValueSet.ContainsComponen
 
  public static void Remove(this List<ValueSet.ContainsComponent> dest, string system, string code)
  {
+ var children = dest.Where(c => c.System == system && c.Code == code).SelectMany(c => c.Contains).ToList();
  dest.RemoveAll(c => c.System == system && c.Code == code);
 
+ //add children back to the list, they do not necessarily need to be removed when the parent is removed.
+ dest.AddRange(children);
+
  // Look for this code in children too
  foreach (var component in dest)
  {
@@ -334,9 +338,15 @@ public static void Remove(this List<ValueSet.ContainsComponent> dest, string sys
 
  public static void Remove(this List<ValueSet.ContainsComponent> dest, List<ValueSet.ContainsComponent> source)
  {
- //TODO: Pretty unclear what to do with child concepts in the source - they all need to be removed from dest?
  foreach (var sourceConcept in source)
+ {
  dest.Remove(sourceConcept.System, sourceConcept.Code);
+
+ //check if there are children that need to be removed too.
+ if (sourceConcept.Contains.Any())
+ dest.Remove(sourceConcept.Contains);
+ }
+
  }
 
  internal static ValueSet.ContainsComponent ToContainsComponent(this CodeSystem.ConceptDefinitionComponent source, CodeSystem system, ValueSetExpanderSettings settings)