$xmlFragment=$log.CreateDocumentFragment()
$clients = 'Sample1.com','Sample2.com'
$targets = $log.selectnodes('//Data')
for ($i = 0; $i -lt $targets.Count; $i++) {
$rows = $targets[$i].selectnodes(".//Row")
$item = $clients[$i]
$new_node = "<client>$item</client>"
foreach ($row in $rows) {
$xmlFragment.InnerXML=$new_node
$row.PrependChild($xmlFragment)
}
}