diff --git a/src/physics/arcade/PhysicsGroup.js b/src/physics/arcade/PhysicsGroup.js
index 1d41970d7f..447828589c 100644
--- a/src/physics/arcade/PhysicsGroup.js
+++ b/src/physics/arcade/PhysicsGroup.js
@@ -87,11 +87,10 @@ var PhysicsGroup = new Class({
         }
         else
         {
-            // config is not defined and children is not a plain object nor an array of plain objects
-            config = {
-                internalCreateCallback: this.createCallbackHandler,
-                internalRemoveCallback: this.removeCallbackHandler
-            };
+            // children is not a plain object nor an array of plain objects
+            config = config || {};
+            config.internalCreateCallback = this.createCallbackHandler;
+            config.internalRemoveCallback = this.removeCallbackHandler;
         }
 
         /**
diff --git a/src/physics/arcade/StaticPhysicsGroup.js b/src/physics/arcade/StaticPhysicsGroup.js
index ae9fba2a57..06dc1f3464 100644
--- a/src/physics/arcade/StaticPhysicsGroup.js
+++ b/src/physics/arcade/StaticPhysicsGroup.js
@@ -88,11 +88,10 @@ var StaticPhysicsGroup = new Class({
         }
         else
         {
-            // config is not defined and children is not a plain object nor an array of plain objects
-            config = {
-                internalCreateCallback: this.createCallbackHandler,
-                internalRemoveCallback: this.removeCallbackHandler
-            };
+            // children is not a plain object nor an array of plain objects
+            config = config || {};
+            config.internalCreateCallback = this.createCallbackHandler;
+            config.internalRemoveCallback = this.removeCallbackHandler;
         }
 
         /**