在一个Visual Studio开发服务器中运行多个web应用程序?

I have 2 ASP.Net MVC web application, ParentSite and ChidSite. ParentSite has a page which will open a pop-up window which will navigate to child site, when childpage is done it notifies the parent page. However I'm getting a cross domain error as I have 2 ASP.Net MVC web application, ParentSit