Parentals and breeders and 'rents, oh my!

Today I couldn't stop missing my sister (and her two kids, with whom I will be spending time in February, woo hoo! Her hubby will be away at a conference), so I popped over to babble.com (to avoid work and find something to giggle with her about later: The 33 Most Ridiculous Toys of All Time -- I like #s 17 and 11) where I also found an article by Mark Peters about how best to refer to people who have created other people (without using the pedestrian, stodgy, standalone, two-syllable "parent".) Hey, I'll be one eventually... why not start the learning process now?

So I got to thinking -- if the term "parental units" gave birth to "maternal unit" and "paternal unit", what would be the proper way to refer to two mommies? The way I figure it, "marentals" would be the way to go. (I figured this out after magically being unable to speak the word "maternal", after three tries. I guess it will take me some time to get out of the baby shower mentality.) However, I'm unable to think of a word to refer to two daddies. Can you? I thought of "darentals", but that just sounds, well, stupid...