Silverlight: get children of a control

Question:

How to get in Silverlight all children of a given control?
Get all children of a given type from a control in Silverlight 4?

Silverlight: Cross domain WCF service calls

Question:

How to access a WCF service on domain A from a Silverlight application on domain B?
I have a silverlight app on localhost:8008 and a WCF service on localhost:8080. My silverlight app cannot access the WCF service. What can I do?