DataMapper ORM - How to get all of a model and each instance's related data

[eluser]WanWizard[/eluser]
For the first one it would be something like:

Code:

$product = new Product;
$product->include_related('photo')->where_related_photo('splash', 1)->get();

and for getting all photo's for a product:

Code:

$photo = new Photo;
$photo->where('product_id', $productid)->get();