I'm trying to do a simple grouping and then post the siblings but I'm
a little bit confused.

I have the following XML:
<?xml version="1.0" encoding="UTF-8"?>
<Entries>
   <entry>
      <First>First Group</First>
      <Second>sample data I</Second>
   </entry>
   <entry>
       <First>Second Group</First>
      <Second>sample data II</Second>
   </entry>
    <entry>
        <First>First Group</First>
        <Second>sample data III</Second>
    </entry>
</Entries>

I'm trying to group the data using the <First> tag and then show all
the <Second> tags data.
Example of the result:

<Entries>
   <entryTransformation>
      <data>First Group</data>
      <secondaryData>sample data I</secondaryData>
      <secondaryData>sample data III</secondaryData>
   </entryTransformation>
   <entryTransformation>
      <data>Second Group</data>
      <secondaryData>sample data II</secondaryData>
   </entryTransformation>
</Entries>

I'm using
<xsl:for-each-group select="/Entries/entryTransformation/data" group-by=".">
To make the grouping, but then I don't know how to iterate the
<Second> elements.

t:\ftemp>type andy.xml
<?xml version="1.0" encoding="UTF-8"?>
<Entries>
   <entry>
      <First>First Group</First>
      <Second>sample data I</Second>
   </entry>
   <entry>
       <First>Second Group</First>
      <Second>sample data II</Second>
   </entry>
    <entry>
        <First>First Group</First>
        <Second>sample data III</Second>
    </entry>
</Entries>

t:\ftemp>xslt2 andy.xml andy.xsl
<?xml version="1.0" encoding="UTF-8"?>
<Entries>
   <entryTransformation>
      <data>First Group</data>
      <secondaryData>sample data I</secondaryData>
      <secondaryData>sample data III</secondaryData>
   </entryTransformation>
   <entryTransformation>
      <data>Second Group</data>
      <secondaryData>sample data II</secondaryData>
   </entryTransformation>
</Entries>
t:\ftemp>type andy.xsl
<?xml version="1.0" encoding="US-ASCII"?>
<xsl:stylesheet xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
                version="2.0">

<xsl:template match="/Entries">
  <Entries>
    <xsl:for-each-group select="entry" group-by="First">
      <entryTransformation>
        <data><xsl:value-of select="First"/></data>
        <xsl:for-each select="current-group()">
          <secondaryData>
            <xsl:value-of select="Second"/>
          </secondaryData>
        </xsl:for-each>
      </entryTransformation>
    </xsl:for-each-group>
  </Entries>
</xsl:template>

</xsl:stylesheet>
t:\ftemp>

--
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