Display next ChildNode using AS?

Ok, I have this extremely simple XML displaying movie I made using the Display XML in Flash tutorial, and now I want to know what to do so that I can click on a button and make the whole data change to the next ChildNode. For example,

 <?xml version="1.0"?> 
<inventors>
 <person>
  <name>Thomas Edison</name>
  <comment>Inventor of many things such as the incandescent lightbulb.</comment>
 </person>
 <person>
  <name>Doug Engelbart</name>
  <comment>Invented the mouse at the Stanford Research Institute</comment>
 </person>
</inventors>

it first displays the first person named “Thomas” and all of its info, and when I click a “next” button I want it to display the info of the next person shown in the XML file. I think it is done using [color=#0000d0]nextSibling [/color][color=black]or something like that… but I dont know how to use it… any ideas?[/color]