If you're talking a "real" modal dialog, be aware it is internet explorer only.
That said, you probably have your order backwards. You have to first refresh, reload, or redirect (as you desire) the opener, then you can close the child (modal window).
If this post contains any code, I may or may not have tested it. It's probably just example code, so no getting knickers in a bunch over a typo, OK? If it doesn't have basic error checking in it, such as object detection or checking if objects are null before using them, put that in there. I'm giving examples, not typing up your whole app for you. You run code at your own risk.
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