diff --git a/src/Pyramid-Bloc/PyramidAddChildCommand.class.st b/src/Pyramid-Bloc/PyramidAddChildCommand.class.st
index 5b13af9..05e2cb5 100644
--- a/src/Pyramid-Bloc/PyramidAddChildCommand.class.st
+++ b/src/Pyramid-Bloc/PyramidAddChildCommand.class.st
@@ -12,6 +12,9 @@ PyramidAddChildCommand >> commandInverse [
 
 { #category : #'as yet unclassified' }
 PyramidAddChildCommand >> setValueFor: aBlElement with: aChildToAdd [
-
-	aBlElement addChild: aChildToAdd
+    | index |
+    index := aChildToAdd userData at: #removedAtIndex ifAbsent: [ 0 ].
+    (index = 0 or: [ index > aBlElement children size ])
+        ifTrue: [ aBlElement addChild: aChildToAdd ]
+        ifFalse: [ aBlElement addChild: aChildToAdd at: index ]
 ]
diff --git a/src/Pyramid-Bloc/PyramidAddChildrenCommand.class.st b/src/Pyramid-Bloc/PyramidAddChildrenCommand.class.st
index 1c14656..520fe7c 100644
--- a/src/Pyramid-Bloc/PyramidAddChildrenCommand.class.st
+++ b/src/Pyramid-Bloc/PyramidAddChildrenCommand.class.st
@@ -12,6 +12,6 @@ PyramidAddChildrenCommand >> commandInverse [
 
 { #category : #'as yet unclassified' }
 PyramidAddChildrenCommand >> setValueFor: aBlElement with: aChildrenToAdd [
-
-	aBlElement addChildren: aChildrenToAdd
+    aChildrenToAdd do: [ :child |
+        aBlElement addChild: child ]
 ]
diff --git a/src/Pyramid-Bloc/PyramidRemoveSelectedElementsCommand.class.st b/src/Pyramid-Bloc/PyramidRemoveSelectedElementsCommand.class.st
index 2beae59..9e281af 100644
--- a/src/Pyramid-Bloc/PyramidRemoveSelectedElementsCommand.class.st
+++ b/src/Pyramid-Bloc/PyramidRemoveSelectedElementsCommand.class.st
@@ -15,18 +15,23 @@ PyramidRemoveSelectedElementsCommand >> getValueFor: anElementOfSelection [
 
 { #category : #'as yet unclassified' }
 PyramidRemoveSelectedElementsCommand >> mementoFor: anElement withArguments: anArgument [
-
-	(anArgument includes: anElement) ifTrue: [
-		^ PyramidCommandMemento new
-			  command: PyramidRemoveFromCollectionCommand new commandInverse;
-			  target: anArgument;
-			  arguments: anElement;
-			  yourself ].
-	^ PyramidCommandMemento new
-		  command: PyramidRemoveChildCommand new commandInverse;
-		  target: anElement parent;
-		  arguments: anElement;
-		  yourself
+    | index |
+    "Save index before removing"
+    index := anElement parent
+        ifNotNil: [ :p | p children indexOf: anElement ]
+        ifNil: [ 0 ].
+    anElement userData at: #removedAtIndex put: index.
+    (anArgument includes: anElement) ifTrue: [
+        ^ PyramidCommandMemento new
+            command: PyramidRemoveFromCollectionCommand new commandInverse;
+            target: anArgument;
+            arguments: anElement;
+            yourself ].
+    ^ PyramidCommandMemento new
+        command: PyramidRemoveChildCommand new commandInverse;
+        target: anElement parent;
+        arguments: anElement;
+        yourself
 ]
 
 { #category : #accessing }
diff --git a/src/Pyramid-Tests/PyramidUndoRemoveChildCommandTest.class.st b/src/Pyramid-Tests/PyramidUndoRemoveChildCommandTest.class.st
new file mode 100644
index 0000000..76ffedc
--- /dev/null
+++ b/src/Pyramid-Tests/PyramidUndoRemoveChildCommandTest.class.st
@@ -0,0 +1,87 @@
+Class {
+	#name : #PyramidUndoRemoveChildCommandTest,
+	#superclass : #TestCase,
+	#category : #'Pyramid-Tests-cases-plugin-bloc'
+}
+
+{ #category : #tests }
+PyramidUndoRemoveChildCommandTest >> testUndoRemoveAllChildrenRestoresIndex [
+
+	| history commandExecutor parent child1 child2 child3 child4|
+	parent := BlElement new.
+	child1 := BlElement new.
+	child2 := BlElement new.
+	child3 := BlElement new.
+	child4 := BlElement new.
+	parent addChildren: {child1. child2 .child3. child4}.
+
+	history := PyramidHistory new.
+	commandExecutor := PyramidHistoryCommandExecutor new
+		                   history: history;
+		                   wrappee: PyramidMainCommandExecutor new;
+		                   yourself.
+	commandExecutor
+		use: PyramidRemoveSelectedElementsCommand new
+		on: {
+				child4.
+				child2.
+				child1 }
+		with: { parent }.
+
+	self deny: (parent children includes: child2).
+	self deny: (parent children includes: child1).
+	self deny: (parent children includes: child4).
+
+	"Undo"
+	history undo.
+
+	self assert: (parent children includes: child1).
+	self assert: (parent children includes: child2).
+	self assert: (parent children indexOf: child1) equals: 1.
+	self assert: (parent children indexOf: child2) equals: 2.
+	self assert: (parent children indexOf: child4) equals: 4
+]
+
+{ #category : #tests }
+PyramidUndoRemoveChildCommandTest >> testUndoRemoveChildRestoresIndex [
+
+	| history commandExecutor parent child1 child2 child3 |
+	
+	parent := BlElement new.
+	child1 := BlElement new.
+	child2 := BlElement new.
+	child3 := BlElement new.
+	parent addChild: child1.
+	parent addChild: child2.
+	parent addChild: child3.
+	
+	history := PyramidHistory new.
+	commandExecutor := PyramidHistoryCommandExecutor new
+		                   history: history;
+		                   wrappee: PyramidMainCommandExecutor new;
+		                   yourself. 
+		
+	commandExecutor
+		use: PyramidRemoveSelectedElementsCommand new
+		on: { child2 }
+		with: { parent }.
+		
+	self deny: (parent children includes: child2). 
+	
+	"Undo"
+	history undo.
+	
+	self assert: (parent children includes: child2).
+	self assert: (parent children indexOf: child2) equals: 2. 
+	
+	"Redo"
+	history redo.
+	
+	self deny: (parent children includes: child2). 
+	
+	"Undo"
+	history undo.
+	
+	self assert: (parent children includes: child2).
+	self assert: (parent children indexOf: child2) equals: 2
+]
diff --git a/src/Pyramid/PyramidCompositeMemento.class.st b/src/Pyramid/PyramidCompositeMemento.class.st
index f3eb07f..8ec7456 100644
--- a/src/Pyramid/PyramidCompositeMemento.class.st
+++ b/src/Pyramid/PyramidCompositeMemento.class.st
@@ -34,5 +34,10 @@ PyramidCompositeMemento >> mementos: anObject [
 { #category : #'window management' }
 PyramidCompositeMemento >> restore [
 
-	self mementos do: [ :each | each restore ]
+	(self mementos allSatisfy: [ :m | m arguments isKindOf: BlElement ])
+		ifFalse: [ self mementos do: [ :each | each restore ]. ^ self ].
+	(self mementos asSortedCollection: [ :a :b |
+			 (a arguments userData at: #removedAtIndex ifAbsent: [ 0 ])
+			 < (b arguments userData at: #removedAtIndex ifAbsent: [ 0 ]) ])
+		do: [ :each | each restore ]
 ]