Technically, you can fit three car seats into the back of a Taurus, but I wouldn't recommend it. It will make your life very, very hard and might even cause you to utter (or proclaim depending on your level of anger control) words your kids don't need to learn. I may be facing this situation soon unless I can find an abandoned one of these: a van.
Either way, we need to get something bigger than what we currently have. Or, I may look like this: a crazy woman!