diff --git a/UsbDk/FilterDevice.cpp b/UsbDk/FilterDevice.cpp
index c5228b7..eb345f1 100644
--- a/UsbDk/FilterDevice.cpp
+++ b/UsbDk/FilterDevice.cpp
@@ -170,6 +170,51 @@ void CDeviceRelations::PushBack(PDEVICE_OBJECT Relation)
     m_Relations->Objects[m_PushPosition++] = Relation;
 }
 
+void CUsbDkFilterDevice::DropRemovedDevices(const CDeviceRelations &Relations)
+{
+    m_ChildrenDevices.ForEachDetachedIf([&Relations](CUsbDkChildDevice *Child) { return !Relations.Contains(*Child); },
+                                        [](CUsbDkChildDevice *Child) -> bool { delete Child; return true; });
+}
+
+void CUsbDkFilterDevice::AddNewDevices(const CDeviceRelations &Relations)
+{
+    Relations.ForEachIf([this](PDEVICE_OBJECT PDO){ return !IsChildRegistered(PDO); },
+                        [this](PDEVICE_OBJECT PDO){ RegisterNewChild(PDO); return true; });
+}
+
+void CUsbDkFilterDevice::RegisterNewChild(PDEVICE_OBJECT PDO)
+{
+    CWdmDeviceAccess pdoAccess(PDO);
+    CObjHolder<CRegText> DevID(pdoAccess.GetDeviceID());
+
+    if (!DevID || DevID->empty())
+    {
+        TraceEvents(TRACE_LEVEL_INFORMATION, TRACE_FILTERDEVICE, "%!FUNC! No Device IDs read");
+        return;
+    }
+
+    CObjHolder<CRegText> InstanceID(pdoAccess.GetInstanceID());
+
+    if (!InstanceID || InstanceID->empty())
+    {
+        TraceEvents(TRACE_LEVEL_INFORMATION, TRACE_FILTERDEVICE, "%!FUNC! No Instance ID read");
+        return;
+    }
+
+    CUsbDkChildDevice *Device = new CUsbDkChildDevice(DevID, InstanceID, PDO);
+
+    if (Device == nullptr)
+    {
+        TraceEvents(TRACE_LEVEL_INFORMATION, TRACE_FILTERDEVICE, "%!FUNC! Cannot allocate child device instance");
+        return;
+    }
+
+    DevID.detach();
+    InstanceID.detach();
+
+    m_ChildrenDevices.PushBack(Device);
+}
+
 void CUsbDkFilterDevice::ClearChildrenList()
 {
     m_ChildrenDevices.ForEachDetached([](CUsbDkChildDevice* Child) { delete Child; return true; });
diff --git a/UsbDk/FilterDevice.h b/UsbDk/FilterDevice.h
index 9e9f7f5..2164acc 100644
--- a/UsbDk/FilterDevice.h
+++ b/UsbDk/FilterDevice.h
@@ -34,9 +34,12 @@ public:
     PCWCHAR InstanceID() const { return *m_InstanceID->begin(); }
     PDEVICE_OBJECT PDO() const { ObReferenceObject(m_PDO); return m_PDO; }
 
-     bool Match(PCWCHAR deviceID, PCWCHAR instanceID)
+     bool Match(PCWCHAR deviceID, PCWCHAR instanceID) const
      { return m_DeviceID->Match(deviceID) && m_InstanceID->Match(instanceID); }
 
+     bool Match(PDEVICE_OBJECT PDO) const
+     { return m_PDO == PDO; }
+
     void Dump();
 
     PLIST_ENTRY GetListEntry()
@@ -55,6 +58,8 @@ private:
     CUsbDkChildDevice& operator= (const CUsbDkChildDevice&) = delete;
 };
 
+class CDeviceRelations;
+
 class CUsbDkFilterDevice : private CWdfDevice, public CAllocatable<NonPagedPool, 'DFHR'>
 {
 public:
@@ -101,6 +106,12 @@ private:
     bool ShouldAttach();
     void ClearChildrenList();
 
+    void DropRemovedDevices(const CDeviceRelations &Relations);
+    void AddNewDevices(const CDeviceRelations &Relations);
+    bool IsChildRegistered(PDEVICE_OBJECT PDO)
+    { return !m_ChildrenDevices.ForEachIf([PDO](CUsbDkChildDevice *Child){ return Child->Match(PDO); }, ConstFalse); }
+    void RegisterNewChild(PDEVICE_OBJECT PDO);
+
     CWdfWorkitem m_QDRCompletionWorkItem;
 
     PIRP m_QDRIrp = nullptr;