sqldatasource question in vb.net code

I am trying to set parameters for my datasource in my page_load event. Why is this not working?
dsbirthday.SelectCommand = "SELECT [family], [bday], [daysleft], [age_id], [wp] " + _ "FROM [tbl_family] WHERE s = @s AND f = @f ORDER BY [daysleft]" dsbirthday.SelectParameters.Add("@s", "Y") dsbirthday.SelectParameters.Add("@f", Session("main_family_code")) <SelectParameters> <asp:Parameter Name="show" Type="String" /> <asp:Parameter Name="f_mainid" Type="String" /> </SelectParameters>



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