Combining two Elements in XML document

Hello,

I have a simple question - for those who have used LINQ to XML much... How can I combine to Elements as one?

E.g.

<Root>

   <ChildOne>Value X</ChildOne>

   <ChildTwo>Value Y</ChildTwo>

   <ChildOne>Value 1</ChildOne>

   <ChildTwo>Value 2</ChildTwo>

</Root>

into this:

<Root>

   <Child>Value X Value Y</Child>

   <Child>Value 1 Value 2</Child>

</Root>

Thanks

Mick