diff --git a/lib/resource/PhysicalResource.d.ts b/lib/resource/PhysicalResource.d.ts
index 3340ef88..abfd9be1 100644
--- a/lib/resource/PhysicalResource.d.ts
+++ b/lib/resource/PhysicalResource.d.ts
@@ -3,7 +3,7 @@ import { ResourceChildren } from './ResourceChildren';
 import { FSManager, FSPath } from '../manager/FSManager';
 export declare abstract class PhysicalResource extends StandardResource {
     realPath: string;
-    constructor(realPath: string, parent: IResource, fsManager: FSManager);
+    constructor(realPath: string, parent?: IResource, fsManager?: FSManager);
     abstract create(callback: SimpleCallback): any;
     abstract delete(callback: SimpleCallback): any;
     moveTo(to: FSPath, callback: Return2Callback<FSPath, FSPath>): void;
@@ -21,7 +21,7 @@ export declare abstract class PhysicalResource extends StandardResource {
 }
 export declare class PhysicalFolder extends PhysicalResource {
     children: ResourceChildren;
-    constructor(realPath: string, parent: IResource, fsManager: FSManager);
+    constructor(realPath: string, parent?: IResource, fsManager?: FSManager);
     type(callback: ReturnCallback<ResourceType>): void;
     create(callback: SimpleCallback): void;
     delete(callback: SimpleCallback): void;
@@ -35,7 +35,7 @@ export declare class PhysicalFolder extends PhysicalResource {
     getChildren(callback: ReturnCallback<IResource[]>): void;
 }
 export declare class PhysicalFile extends PhysicalResource {
-    constructor(realPath: string, parent: IResource, fsManager: FSManager);
+    constructor(realPath: string, parent?: IResource, fsManager?: FSManager);
     type(callback: ReturnCallback<ResourceType>): void;
     create(callback: SimpleCallback): void;
     delete(callback: SimpleCallback): void;
diff --git a/lib/resource/PhysicalResource.js b/lib/resource/PhysicalResource.js
index d621beb4..cf7bd7d5 100644
--- a/lib/resource/PhysicalResource.js
+++ b/lib/resource/PhysicalResource.js
@@ -93,7 +93,12 @@ var PhysicalFolder = (function (_super) {
         Resource_1.StandardResource.sizeOfSubFiles(this, callback);
     };
     PhysicalFolder.prototype.addChild = function (resource, callback) {
-        this.children.add(resource, callback);
+        var _this = this;
+        this.children.add(resource, function (e) {
+            if (!e)
+                resource.parent = _this;
+            callback(e);
+        });
     };
     PhysicalFolder.prototype.removeChild = function (resource, callback) {
         this.children.remove(resource, callback);
diff --git a/lib/resource/Resource.js b/lib/resource/Resource.js
index ae387278..ca3cb52d 100644
--- a/lib/resource/Resource.js
+++ b/lib/resource/Resource.js
@@ -125,8 +125,13 @@ var StandardResource = (function () {
         this.dateLastModified = Date.now();
     };
     StandardResource.prototype.removeFromParent = function (callback) {
-        if (this.parent)
-            this.parent.removeChild(this, callback);
+        var _this = this;
+        var parent = this.parent;
+        if (parent)
+            parent.removeChild(this, function (e) {
+                if (_this.parent === parent)
+                    _this.parent = null;
+            });
         else
             callback(null);
     };
diff --git a/lib/resource/RootResource.js b/lib/resource/RootResource.js
index 5fe592d9..54058a78 100644
--- a/lib/resource/RootResource.js
+++ b/lib/resource/RootResource.js
@@ -54,7 +54,12 @@ var RootResource = (function (_super) {
         Resource_1.StandardResource.sizeOfSubFiles(this, callback);
     };
     RootResource.prototype.addChild = function (resource, callback) {
-        this.children.add(resource, callback);
+        var _this = this;
+        this.children.add(resource, function (e) {
+            if (!e)
+                resource.parent = _this;
+            callback(e);
+        });
     };
     RootResource.prototype.removeChild = function (resource, callback) {
         this.children.remove(resource, callback);
diff --git a/lib/resource/VirtualResource.d.ts b/lib/resource/VirtualResource.d.ts
index ea23fbc5..df34ce12 100644
--- a/lib/resource/VirtualResource.d.ts
+++ b/lib/resource/VirtualResource.d.ts
@@ -3,7 +3,7 @@ import { ResourceChildren } from './ResourceChildren';
 import { FSManager, FSPath } from '../manager/FSManager';
 export declare abstract class VirtualResource extends StandardResource {
     name: string;
-    constructor(name: string, parent: IResource, fsManager?: FSManager);
+    constructor(name: string, parent?: IResource, fsManager?: FSManager);
     create(callback: SimpleCallback): void;
     delete(callback: SimpleCallback): void;
     moveTo(to: FSPath, callback: Return2Callback<FSPath, FSPath>): void;
@@ -21,7 +21,7 @@ export declare abstract class VirtualResource extends StandardResource {
 }
 export declare class VirtualFolder extends VirtualResource {
     children: ResourceChildren;
-    constructor(name: string, parent: IResource, fsManager?: FSManager);
+    constructor(name: string, parent?: IResource, fsManager?: FSManager);
     type(callback: ReturnCallback<ResourceType>): void;
     append(data: Int8Array, callback: SimpleCallback): void;
     write(data: Int8Array, callback: SimpleCallback): void;
@@ -34,7 +34,7 @@ export declare class VirtualFolder extends VirtualResource {
 }
 export declare class VirtualFile extends VirtualResource {
     content: Int8Array;
-    constructor(name: string, parent: IResource, fsManager?: FSManager);
+    constructor(name: string, parent?: IResource, fsManager?: FSManager);
     type(callback: ReturnCallback<ResourceType>): void;
     create(callback: SimpleCallback): void;
     delete(callback: SimpleCallback): void;
diff --git a/lib/resource/VirtualResource.js b/lib/resource/VirtualResource.js
index ac6c0bff..97db341c 100644
--- a/lib/resource/VirtualResource.js
+++ b/lib/resource/VirtualResource.js
@@ -67,7 +67,12 @@ var VirtualFolder = (function (_super) {
         Resource_1.StandardResource.sizeOfSubFiles(this, callback);
     };
     VirtualFolder.prototype.addChild = function (resource, callback) {
-        this.children.add(resource, callback);
+        var _this = this;
+        this.children.add(resource, function (e) {
+            if (!e)
+                resource.parent = _this;
+            callback(e);
+        });
     };
     VirtualFolder.prototype.removeChild = function (resource, callback) {
         this.children.remove(resource, callback);
diff --git a/src/resource/PhysicalResource.ts b/src/resource/PhysicalResource.ts
index ede4c49e..6cc04c7a 100644
--- a/src/resource/PhysicalResource.ts
+++ b/src/resource/PhysicalResource.ts
@@ -9,7 +9,7 @@ export abstract class PhysicalResource extends StandardResource
 {
     realPath : string
     
-    constructor(realPath : string, parent : IResource, fsManager : FSManager)
+    constructor(realPath : string, parent ?: IResource, fsManager ?: FSManager)
     {
         super(parent, fsManager);
 
@@ -63,7 +63,7 @@ export class PhysicalFolder extends PhysicalResource
 {
     children : ResourceChildren
 
-    constructor(realPath : string, parent : IResource, fsManager : FSManager)
+    constructor(realPath : string, parent ?: IResource, fsManager ?: FSManager)
     {
         super(realPath, parent, fsManager);
 
@@ -128,7 +128,11 @@ export class PhysicalFolder extends PhysicalResource
     // ****************************** Children ****************************** //
     addChild(resource : IResource, callback : SimpleCallback)
     {
-        this.children.add(resource, callback);
+        this.children.add(resource, (e) => {
+            if(!e)
+                resource.parent = this;
+            callback(e);
+        });
     }
     removeChild(resource : IResource, callback : SimpleCallback)
     {
@@ -142,7 +146,7 @@ export class PhysicalFolder extends PhysicalResource
 
 export class PhysicalFile extends PhysicalResource
 {
-    constructor(realPath : string, parent : IResource, fsManager : FSManager)
+    constructor(realPath : string, parent ?: IResource, fsManager ?: FSManager)
     {
         super(realPath, parent, fsManager);
     }
diff --git a/src/resource/Resource.ts b/src/resource/Resource.ts
index ec8217f4..93ed3833 100644
--- a/src/resource/Resource.ts
+++ b/src/resource/Resource.ts
@@ -246,8 +246,12 @@ export abstract class StandardResource implements IResource
 
     protected removeFromParent(callback : SimpleCallback)
     {
-        if(this.parent)
-            this.parent.removeChild(this, callback);
+        const parent = this.parent;
+        if(parent)
+            parent.removeChild(this, (e) => {
+                if(this.parent === parent) // this.parent didn't change
+                    this.parent = null;
+            });
         else
             callback(null);
     }
diff --git a/src/resource/RootResource.ts b/src/resource/RootResource.ts
index 95518bf8..9f6e5d12 100644
--- a/src/resource/RootResource.ts
+++ b/src/resource/RootResource.ts
@@ -67,7 +67,11 @@ export class RootResource extends StandardResource
     // ****************************** Children ****************************** //
     addChild(resource : IResource, callback : SimpleCallback)
     {
-        this.children.add(resource, callback);
+        this.children.add(resource, (e) => {
+            if(!e)
+                resource.parent = this;
+            callback(e);
+        });
     }
     removeChild(resource : IResource, callback : SimpleCallback)
     {
diff --git a/src/resource/VirtualResource.ts b/src/resource/VirtualResource.ts
index 69767ca6..408f540d 100644
--- a/src/resource/VirtualResource.ts
+++ b/src/resource/VirtualResource.ts
@@ -10,7 +10,7 @@ export abstract class VirtualResource extends StandardResource
 {
     name : string
 
-    constructor(name : string, parent : IResource, fsManager ?: FSManager)
+    constructor(name : string, parent ?: IResource, fsManager ?: FSManager)
     {
         super(parent, fsManager ? fsManager : new VirtualFSManager());
 
@@ -61,7 +61,7 @@ export class VirtualFolder extends VirtualResource
 {
     children : ResourceChildren
 
-    constructor(name : string, parent : IResource, fsManager ?: FSManager)
+    constructor(name : string, parent ?: IResource, fsManager ?: FSManager)
     {
         super(name, parent, fsManager);
 
@@ -99,7 +99,11 @@ export class VirtualFolder extends VirtualResource
     // ****************************** Children ****************************** //
     addChild(resource : IResource, callback : SimpleCallback)
     {
-        this.children.add(resource, callback);
+        this.children.add(resource, (e) => {
+            if(!e)
+                resource.parent = this;
+            callback(e);
+        });
     }
     removeChild(resource : IResource, callback : SimpleCallback)
     {
@@ -115,7 +119,7 @@ export class VirtualFile extends VirtualResource
 {
     content : Int8Array
 
-    constructor(name : string, parent : IResource, fsManager ?: FSManager)
+    constructor(name : string, parent ?: IResource, fsManager ?: FSManager)
     {
         super(name, parent, fsManager);
 
diff --git a/test/tests/listRootFolder.js b/test/tests/listRootFolder.js
index 55963039..011129ca 100644
--- a/test/tests/listRootFolder.js
+++ b/test/tests/listRootFolder.js
@@ -11,7 +11,7 @@ module.exports = (test, options, index) => test('list root folder', _isValid =>
     }
 
     var server = new webdav.WebDAVServer();
-    server.rootResource.addChild(new webdav.VirtualFile('file.txt', server.rootResource, null), e => {
+    server.rootResource.addChild(new webdav.VirtualFile('file.txt', server.rootResource), e => {
         if(e)
         {
             isValid(false, e)
diff --git a/test/tests/makeFolder.js b/test/tests/makeFolder.js
index 9ea637e1..988b3674 100644
--- a/test/tests/makeFolder.js
+++ b/test/tests/makeFolder.js
@@ -21,7 +21,7 @@ module.exports = (test, options, index) => test('make a folder', _isValid =>
     }
     
     var server = new webdav.WebDAVServer();
-    server.rootResource.addChild(new webdav.VirtualFile('testFile.txt', server.rootResource, null), e => {
+    server.rootResource.addChild(new webdav.VirtualFile('testFile.txt', server.rootResource), e => {
         if(e)
         {
             isValid(false, e)
diff --git a/test/tests/readVirtualFile.js b/test/tests/readVirtualFile.js
index f4eaf729..e3d3e2e9 100644
--- a/test/tests/readVirtualFile.js
+++ b/test/tests/readVirtualFile.js
@@ -23,7 +23,7 @@ module.exports = (test, options, index) => test('read a virtual file', _isValid
     var testValue = 'this is the content!';
 
     var server = new webdav.WebDAVServer();
-    var file = new webdav.VirtualFile('testFile.txt', server.rootResource, null);
+    var file = new webdav.VirtualFile('testFile.txt', server.rootResource);
     file.content = testValue;
     server.rootResource.addChild(file, e => {
         if(e)
diff --git a/test/tests/statVirtualFile.js b/test/tests/statVirtualFile.js
index 05d1f9d3..9d5ba2f4 100644
--- a/test/tests/statVirtualFile.js
+++ b/test/tests/statVirtualFile.js
@@ -21,7 +21,7 @@ module.exports = (test, options, index) => test('stat of virtual file', _isValid
     }
 
     var server = new webdav.WebDAVServer();
-    server.rootResource.addChild(new webdav.VirtualFile('testFile.txt', server.rootResource, null), e => {
+    server.rootResource.addChild(new webdav.VirtualFile('testFile.txt', server.rootResource), e => {
         if(e)
         {
             isValid(false, e)