gistfile1.diff

# git diff
diff --git a/Nested-Parent-Template.py b/Nested-Parent-Template.py
index 14311ca..b2d39fb 100644
--- a/Nested-Parent-Template.py
+++ b/Nested-Parent-Template.py
@@ -24,12 +24,12 @@ KeyPair = t.add_parameter(Parameter(

 ChildTemplate1 = t.add_resource(cloudformation.Stack(
     "ChildTempate1",
-    TemplateURL="https://s3.amazonaws.com/my.first.bucket.test/ChildJSON",
+    TemplateURL="https://s3.amazonaws.com/phobologic-test-bucket/ChildJSON",
     Parameters={
-        "ELBSubnets": Ref(ELBSubnets),
-        "LCSecurityGroups": Ref(LCSecurityGroups),
-        "KeyPair": Ref(KeyPair)
+        "ELBSubnets": Join(",", Ref(ELBSubnets)),
+        "LCSecurityGroups": Join(",", Ref(LCSecurityGroups)),
+        "LCKeyPair": Ref(KeyPair)
     }
 ))

-print(t.to_json())
\ No newline at end of file
+print(t.to_json())
diff --git a/ParentJSON b/ParentJSON
index fc19c56..9a98b38 100644
--- a/ParentJSON
+++ b/ParentJSON
@@ -20,16 +20,26 @@
             "Properties": {
                 "Parameters": {
                     "ELBSubnets": {
-                        "Ref": "ELBSubnets"
+                        "Fn::Join": [
+                            ",",
+                            {
+                                "Ref": "ELBSubnets"
+                            }
+                        ]
                     },
-                    "KeyPair": {
+                    "LCKeyPair": {
                         "Ref": "LCKeyPair"
                     },
                     "LCSecurityGroups": {
-                        "Ref": "LCSecurityGroups"
+                        "Fn::Join": [
+                            ",",
+                            {
+                                "Ref": "LCSecurityGroups"
+                            }
+                        ]
                     }
                 },
-                "TemplateURL": "https://s3.amazonaws.com/my.first.bucket.test/ChildJSON"
+                "TemplateURL": "https://s3.amazonaws.com/phobologic-test-bucket/ChildJSON"
             },
             "Type": "AWS::CloudFormation::Stack"