Crashing on screen orientation change

[Nidhee]

It is crashing on orientation change. Here is the log -
12-18 12:07:53.301: E/AndroidRuntime(1325): FATAL EXCEPTION: main
12-18 12:07:53.301: E/AndroidRuntime(1325): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.vp.childfragments/com.vp.childfragments.MainActivity}: android.support.v4.app.Fragment$InstantiationException: Unable to instantiate fragment com.vp.childfragments.fragments.ChildFragment: make sure class name exists, is public, and has an empty constructor that is public
12-18 12:07:53.301: E/AndroidRuntime(1325): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1647)
12-18 12:07:53.301: E/AndroidRuntime(1325): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:1663)
12-18 12:07:53.301: E/AndroidRuntime(1325): at android.app.ActivityThread.handleRelaunchActivity(ActivityThread.java:2832)
12-18 12:07:53.301: E/AndroidRuntime(1325): at android.app.ActivityThread.access$1600(ActivityThread.java:117)
12-18 12:07:53.301: E/AndroidRuntime(1325): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:935)
12-18 12:07:53.301: E/AndroidRuntime(1325): at android.os.Handler.dispatchMessage(Handler.java:99)
12-18 12:07:53.301: E/AndroidRuntime(1325): at android.os.Looper.loop(Looper.java:130)
12-18 12:07:53.301: E/AndroidRuntime(1325): at android.app.ActivityThread.main(ActivityThread.java:3683)
12-18 12:07:53.301: E/AndroidRuntime(1325): at java.lang.reflect.Method.invokeNative(Native Method)
12-18 12:07:53.301: E/AndroidRuntime(1325): at java.lang.reflect.Method.invoke(Method.java:507)
12-18 12:07:53.301: E/AndroidRuntime(1325): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:839)
12-18 12:07:53.301: E/AndroidRuntime(1325): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:597)
12-18 12:07:53.301: E/AndroidRuntime(1325): at dalvik.system.NativeStart.main(Native Method)
12-18 12:07:53.301: E/AndroidRuntime(1325): Caused by: android.support.v4.app.Fragment$InstantiationException: Unable to instantiate fragment com.vp.childfragments.fragments.ChildFragment: make sure class name exists, is public, and has an empty constructor that is public
12-18 12:07:53.301: E/AndroidRuntime(1325): at android.support.v4.app.Fragment.instantiate(Fragment.java:413)
12-18 12:07:53.301: E/AndroidRuntime(1325): at android.support.v4.app.FragmentState.instantiate(Fragment.java:97)
12-18 12:07:53.301: E/AndroidRuntime(1325): at android.support.v4.app.FragmentManagerImpl.restoreAllState(FragmentManager.java:1801)
12-18 12:07:53.301: E/AndroidRuntime(1325): at android.support.v4.app.FragmentActivity.onCreate(FragmentActivity.java:213)
12-18 12:07:53.301: E/AndroidRuntime(1325): at com.vp.childfragments.MainActivity.onCreate(MainActivity.java:46)
12-18 12:07:53.301: E/AndroidRuntime(1325): at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1047)
12-18 12:07:53.301: E/AndroidRuntime(1325): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1611)
12-18 12:07:53.301: E/AndroidRuntime(1325): ... 12 more
12-18 12:07:53.301: E/AndroidRuntime(1325): Caused by: java.lang.InstantiationException: com.vp.childfragments.fragments.ChildFragment
12-18 12:07:53.301: E/AndroidRuntime(1325): at java.lang.Class.newInstanceImpl(Native Method)
12-18 12:07:53.301: E/AndroidRuntime(1325): at java.lang.Class.newInstance(Class.java:1409)
12-18 12:07:53.301: E/AndroidRuntime(1325): at android.support.v4.app.Fragment.instantiate(Fragment.java:402)
12-18 12:07:53.301: E/AndroidRuntime(1325): ... 18 more