ASP.Net User Control Event Bubbling (C#)

Question

Many thanks in advance. I've done my due diligence and researched for 2 days, but can't seem to wrap my mind around what online tutorials describe.

The situation: Lead Programmer ups and quits. Owner of firm knows I've done some (novice) VB.NET on the side and asks me to wire up functionality between 2 custom user controls on his intranet app (written in C#. Small consideration for answering pros -- I'm fluent in Visual Studio...but still learning C#).

Here's a simplified description of controls, but hopefully enough to get us going in the right direction:

UserControl_1 contains multiple linkbuttons that, when clicked, should change the value of the SelectParameter being used by an ObjectDataSource in UserControl_2:

<asp:LinkButton ID="OpenBtn1" runat="server" Text="Show Open Requests" />
<asp:LinkButton ID="ClosedBtn1" runat="server" Text="Show Closed Requests" />

UserControl_2 (GridView with DataSource):

<asp:ObjectDataSource ID="ObjectDataSource1" runat="server"
    SelectMethod="GetDataBy_Status" 
    TypeName="adhoc_TblAdptrs.adhoc_TblAdptr">
    <SelectParameters>
       <asp:Parameter DefaultValue="All" Name="status" Type="String" />
    </SelectParameters>
</asp:ObjectDataSource>

<asp:GridView1 ID="GridView1" runat="server" DataSourceID="ObjectDataSource1" />

What I'd like to do pass a new default value to the SelectParameter of the the ObjectDataSource in UserControl_2. I'm looking forward to a personalized explanation from the pros! Your help is greatly, greatly appreciated!