Is it possible to create a child nodes list, and if two or more of the child nodes have the same related links picked by the Multi Node picker, then they will be combined into a one link.

My idea would be that the combined link would link to another page with thumbnails of all the related links for that particular "client".

Can anyone suggest a possible way of achieving this? Below is my very basic theory on how it might work.
I'm guessing a "count" could also be used?

Cheers, JV

<xsl:choose>
<xsl:when test="$currentPage/groupedLinks/MultiNodePicker/nodeId ??string(nationalClient) = '1'??">
<li class="national_clients">
<a href="{umbraco.library:NiceUrl(@id)} ??Combined link??" title="{@nodeName}">
<img src="{concat(substring-before(clientLogo,'.'), '_thumb_120.jpg')}"/>
</a>
</li>
</xsl:when>
<xsl:otherwise>
<li class="national_clients">
<a href="{umbraco.library:NiceUrl(@id)}" title="{@nodeName}">
<img src="{concat(substring-before(clientLogo,'.'), '_thumb_120.jpg')}"/>
</a>
</li>
</xsl:otherwise>
</xsl:choose>