"When you load a control into a container control,"
This means you have to Control zzzzzzzzzz = yyyyyyyyy.LoadControl() then xxxxxxxx.controls.Add(zzzzzzzzzz);
Note xxxxxxxx and yyyyyyyyy do not need to be the same templateControl (for example I use the page to loadcontrol and then a placeholder within a control on the page to add it.) when the control is added the events are called.