Drop Down Listbox SelectedIndexChanged Event not firing when I programmatically change selection

I have two drop down listboxes (DDL1 and DDL2).  When DDL1 has an index change, DDL2 then has a refresh of list items based off SQL Server SELECT from a table.  The database isn't the problem.  Everything works perfectly when the user selects a new item manually from DDL1.
But in my code, I save the user data from the selection of DDL1 in a separate table.  And then upon rendering of the page (Page_PreRenderComplete), I do a SelectedIndex assignment of the value of what's saved in the db table.  That works just fine, it selects the DDL1 item, but DDL2 is unaffected, as if DDL1's SelectedIndexChanged event isn't called like it would be if manually changed.  How can I get around this?


Thanks in advance. :)
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