Ahh, the Siamese twin plants.... Yes, they should have babies just like they normally would. Since they're both large, I imagine they both have a good root system, so if you pry them apart it shouldn't hurt them. But it won't hurt if you leave them together either. If you feel like practicing your surgeon skills, go for it. Just make a clean slice between them, making sure they both still have roots attached. Leave to dry for a few days, then replant. Chances are they'll never miss a beat. Good luck and let us know the results.