<Data>
   <Group id="1">
      <Child id="1"/>
      <Child id="2"/>
      <Child id="3"/>
   </Group>
   <Group id="2">
      <Child id="1"/>
      <Child id="2"/>
      <Child id="3"/>
   </Group>
</Data>

dim g = From item In _
 XElement.Load("XMLFile.xml", LoadOptions.None)...<Group> _
 Select New nABLE4ConfigInfo.Group(item.@id)

<Serializable> _
Public Class Data

   <Serializable> _
   Public Class Group

       <Serializable> _
       Public Class Child
           <XmlAttribute> _
           Public id As Integer
       End Class


       <XmlArray> _
       Public Child() As Child

       <XmlAttribute> _
       Public id As Integer

   End Class

  <XmlArray> _
  Public Group() As Group
End Class

Dim g = From item In _
      XElement.Load("XMLFile.xml", LoadOptions.None)...<Group> _
             Select New Group(id:=item.@id, _
                   Children:=(From c In item...<Child>  Select c.@id).ToList)