You don't raise an event in another object.  You raise an event in
your object and any other objects that have subscribed to that event
get called.  In this case the child control would have to define an
event and the parent would need to subscribe to that event.

You can access methods and properties in the parent.  If the parent is
an instance of SomeClass or implements a known interface:

Dim myParent As SomeClass = TryCast(Me.Parent, SomeClass)
If myParent IsNot Nothing Then
  myParent.SomeMethod()
...

Interfaces are probably the best way to deal with this, then the child
doesn't have to know the exact class of the parent, you just have to
make sure that all classes that might be the child's parent implement
the interface.