Double load...weird

 I have an aspx page with an ascx (usercontrol) on it.
when I do i test, like place a msgbox('test') in the page_load of the ascx, the msg box always opens twice, when should open once, as the page opens only once. So this suggest that the page_load is doing the event twice ???
Asp.net, happens when I go view in browser !
Any ideas???
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