I know what you should do

Cmon down to Houston for Yorkie Haven Rescue's booth at the dog show next month...I am donating my large pink Snoozer since I no longer need it. It's too big to ship...that's why we couldn't put it in with the raffle, but hopefully someone will want to buy it at the booth to help out YHR!
Seriously though, I think a large snoozer would fit your 3 comfortably, but they might get tangled up or step all over their little sis, ha. Does your car fit a console snoozer? Might work to get a large for Rosie and Mikki (and eventually Lily) but keep Lily in a console seat for now, while she's little, so you can keep a better eye on her. Btw, I'm off to your profile to hunt for new pics of the little beauty.