Let's say I have the following XML file

```
<root></root>

```

and the following file

```
<child>
    <more-childeren> </more-childeren>
</child>

```

How do I insert the second file into the first file to create the following file:

```
<root>
    <child>
        <more-childeren> </more-childeren>
    </child>
</root>

```

I am receiving the second file as a XPathNavigator. What would be the fastest way to insert the XPathNavigator into the XML file?