Thank you all for your input.
As for not taking kids before they're older, it's not going to be possible - I've been pregnant (so in utero is the youngest

), with a 1 year old (and 3 year old), and then up from there. As for going with the new baby - I'm not too worried, since we'll have to have diapers and wipes for the toddler anyway, and tiny baby diapers are smaller and more compact. Plus there's a Sam's and Super Target right down the road, so if we run out, we'll be okay.

And nothing packs and travels like breastmilk. It's always heated up and ready to serve.
I guess it just doesn't intimidate me to bring a baby with us - we traveled with my now toddler when she was 2 months and she did SO great. Far easier than she is now, at 2.
And as for inconveniencing other guests, I think that a baby crying is far less inconvenient than an older child throwing a temper tantrum, or a teen blasting music or slamming doors in the middle of the night, or groups of unsupervised school-age kids running up and down hallways in the hotel.

I mean, when you're in a hotel a lot of things can be distracting or noisy. A tiny baby's squeaky cry isn't going to be any worse than other things - and after all, it's Disney World! People go there and expect there to be kids and babies, yk? Where else can I bring six kids to a restaurant like California Grill and wear capris and sandals?
I found the Baby Bjorn Air - and it looks interesting. I might have to get it and see how the baby likes it. The One Step Ahead link didn't work for me (I think there's an extra "e" in there) but they didn't have it, anyway. I did find it at
Amazon:
http://www.amazon.com/exec/obidos/A...32920/sr=11-1/ref=sr_11_1/102-4859703-7244919
And then, I was considering getting this stroller, which works with our infant carseat:
http://www.gracobaby.com/catalog/product.aspx?modelNumber=6050GRT&CategoryID=2
We have great strollers, but I don't think they'd be very cool or comfortable for the baby. Do you think that I should skip the carseat and just be sure I have a comfy stroller for her? Maybe carry her in the Bjorn on the busses and then put her in a lightweight stroller? We have a twin traveller that I could use for her, as a newborn, but I'd have to get an extended shade for it - like this:
http://www.onestepahead.com/product/86214/325762/117.html#readmore
Would that be enough coverage in a side by side? Or should I get a single stroller that I can pop her carseat in and use an extended shade - and bring a separate stroller for her older sister? (We've done it both ways - twin strollers or two singles, and neither was necessarily easier)