Dog \'Header\' Pens

I don't know if anyone else has thought of this, but I would love to be able to organize my dogs into 'pens'. At the moment, the list of dogs in my kennels is just one long mix. I wondered if the site's coding would allow for us to create 'pens' that we can name bitches, stud dogs, sales, new pups, etc or whatever players wanted, with an option on each dog's page to move it into so-and--so pen.

I know the coding for this is probably huge, but it's a feature that I love on ShowDogs and I didn't know if it would be helpful on here :)