Here are some reading list for you.
http://en.wikipedia.org/wiki/Opaque_pointer
http://en.wikibooks.org/wiki/C%2B%2B_Programming/Idioms#Pointer_To_Implementation_.28pImpl.29
Parent.cpp
#include "stdafx.h"
#include "Parent.h"
#include "Child.h"
Parent::Parent()
{
}
void Parent::GiveBirth()
{
//Child ch = Child(); //Error: incomplete type is not allowed
children.push_back(new Child());
}
Parent::~Parent()
{
}