Unfortunately you can't. Copying data only works with direct parents.
One option would be to place the English store view under a separate store under Manage Stores
and assign it the same category tree as the other English store view.
However, this only works if you're already using different category trees for different stores with the translations on the global level.
[EDIT]
Another option would be to do it via an import. Either use FastSimpleImport (https://github.com/avstudnitz/AvS_FastSimpleImport) that supports category data imports or write a basic script.
Mage::app()->setCurrentStore($storeIdFromWhereToCopy);
$collection = Mage::getResourceModel('catalog/category_collection')
->addFieldToSelect(array('name', 'description', etc...));
$category = Mage::getModel('catalog/category')->setStoreId($storeIdToCopyTo);
foreach ($collection as $item) {
$category->setName($item->getName());
$category->setDescription($item->getDescription());
[...etc...]
$category->save();
}
Before you run scripts and imports like this always remember to make a backup