Wait on all child threads - Silverlight Unit Testing

I'm trying to do a unit test of a silverlight app and the method I call ends up calling another method which does something async. At this point the thread comes all the way out without completely finishing the process O am testing. The test then moves on an fails, is there a way I can take a thread, listen for any threads it creates and then 开发者_开发技巧waits for them to return?

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