How to combine 2 XML files, without copies

Hello,

I am trying to take 2 large XML files and combine them without any duplicate nodes. The code below is as far as I have gotten. I have loaded the 2 files but in the 'For' loop below I am trying to populate an array with all of the 'item' nodes, it bombs. Can anyone give me a nudge with this?

Code:

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<glossary>

<!-- A -->

<item term="AAA" def="Not the American Automobile Association"  />

<item term="ABCCC" def="Definition 1" />

<item term="ABP" def="This means blah" />

</glossary>

---

Code:

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Dim description, filepath
Set xmlDoc1 = CreateObject("Msxml2.DOMDocument")
If xmlDoc1.load("glossary/glossary_data.xml")Then
    'MsgBox "SUCCESS loading XML File" 
Else 
    MsgBox "ERROR loading XML File"  'Error message if file fails to load
End If 

Set xmlDoc2 = CreateObject("Msxml2.DOMDocument")
xmlDoc2.load("glossary2/glossary_data.xml")'file 2
 
Set xmlDoc = CreateObject("Microsoft.XMLDOM")
Dim oneElement
'Dim count = xmlDoc1.documentElement.selectNodes("item").length
Dim elementArray(2)

'for each item in xmlDoc1.documentElement.selectNodes("item")
For i = 0 to xmlDoc1.documentElement.selectNodes("item").length       
        Set objRoot = xmlDoc.createElement("item")
        objRoot.setAttribute "term", "This is the term"
        objRoot.setAttribute "def", "This is the definition"
        elementArray(i) = objRoot
next

xmlDoc.appendChild objRoot


Set objIntro = xmlDoc.createProcessingInstruction("xml","version='1.0'") 
xmlDoc.insertBefore objIntro,xmlDoc.childNodes(0) 

xmlDoc.Save

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