I can't really offer much stroller advice. Sorry!
I think that you could do 2 Epcot days without your DH. There is plenty to do with both kids. Like you said, you need to take breaks, eat, etc. While at Epcot, you could always take a stroll over to the YC/BC/Boardwalk area. There is a super yummy ice cream parlor on the Boardwalk that my family loves.
The Kidcot stations are great but beware....they use sharpies!!! Plus, there are quite a few movies throughout WS that work great for taking a rest in the a/c (France and American Adventure have seats). I've taken a few naps there myself!![]()
That's funny, has Madison always been too old for a stroller at disney? That must be nice!
Taking a stroll over to the boardwalk is a good idea...anything there on the dining plan? That would be a perk, even though I could spend the few dollars on something not on the dining plan!
I have heard about the sharpies and it terrifies me. Really, they couldn't be sponsored by crayola? Or anything washable? Roseart is cheap, I bet they'd love the promotion!

Interesting about the movies. They always bore me to death but J.J. will watch just about anything. If Sydney is napping, that might be a great idea!
The stroller question is tough. I think you'll want to have the double at the parks. As the bus is pulling into the station, put Sydney in the sling and fold the stroller. Have J.J. board in front of you and carry the stroller on. Use a backpack for a diaper bag so you're hands are free. I think you'll find that people will be helpful. We have 3 children and 2 strollers so we've done this before. It isn't easy but the pain only last a few seconds and then you're settled. You'll like having Sydney in the sling on the bus anyway.
Parks. Hmmm. What about one Epcot and one DHS day? There's not a ton at DHS for little kids so your DH wouldn't miss that much. What are your park plans for when he's there?
Amanda
I love the step by step instructions. I needed that! I think you're my DH's new favorite person after you made me stop freaking out about Syd's surgery and now you told me exactly how to handle the stroller. He was very impressed!
I have thought about DHS but the idea of going there when there's not much to do is painful. I mean, really, there's just nothing to do there, especially because I'm worried about Sydney and shows. Our park plans are umm...one long day in each park until we've done them all and then go back and do what we liked again! Haha, I haven't looked at schedules or anything for my new time frame yet.
I'm not much help on the stroller front but it seems like Amanda has that covered!
As for plans without dh, if you don't want him to miss too much you might think of including some activities outside the parks. Maybe some time at DTD followed by a boat ride from DTD to POFQ (these are supposed to be very entertaining and you may even spot an alligator), time on the Boardwalk as suggested above, time at the pool, etc.
I like the idea of hitting a few parades/rides that dh isn't interested in. With hoppers you'll be able to do this and take breaks as well. You might also ask him what he's most looking forward to seeing/doing with the kids. I think that combined with things you don't want to try on your own will leave you with your best options for what to do without him.
I do like the idea of the boat ride, J.J. would think that was SO exciting. We could eat at DTD or POFQ then too. I would LOVE to spend time at the pool but I can't with both of them since neither of them can swim, really. Well, that's not entirely true because J.J. went swimming for the 3rd time ever at a neighbors pool the other day and swam by himself with the swim ring floatie thing. But I think I'd probably be uncomfortable with both of them since I'd only have one hand free to save him. I have thought about it though...we have one of those floatie rings with a seat for Sydney so worst comes to worst she could float there alone for a minute while I'm saving the boy...
I think spending time outside of the parks is probably best, because DH is probably more disney obsessed than I am. It's hard, because I KNOW what would be best is getting to the hotel on Thursday, eating lunch, exploring a little bit and then taking a nap. We have to get up at 4 am to go to the airport, so we'll need one! BUT, I don't think J.J. will nap in a strange place that quickly, and I really need bed rails for the bed and I bet that they won't be there that fast. Frustrating, because what's best probably won't happen!
The stroller question is tough! I can see the advantage of the double - having both kids controlled in one spot. For me, it would boil down to how long I was planning to spend in the park at a stretch. If it was only 2 hours or so, I would probably make J.J. walk and just use the single - afterall, he will have plenty of time to ride when daddy gets there. If I was going to spend 4 hours at a stretch in the parks, then I would go for the double.
As for which parks, I would definately go to Epcot one day. All of the rides you mentioned are good for little ones. I would also do Innoventions, but I would skip Kim Possible. I think I have heard that is better for grade-schoolers and tweens. The other day, I might sleep in, go to DTD and then see the parade at AK. Good luck deciding!
I expect I'll probably be spending a long time in the parks, although it's impossible to say.
J.J. is really into workbooks and school stuff, so I think he would probably love Kim Possible, but I'll keep it in mind that maybe he won't and I won't have a problem just ditching our mission!
I would love to go to DTD, but I don't want to buy anything that early in the trip and I'm not sure toddlers love window shopping. I am considering it though!
In other news...10 weeks from today we will be at WDW! That sounds long since it should have been 5 weeks, but secretly, I don't mind. And that's because I have a list of things that I need to make/do before we go that is crazy long, AND my sewing machine just broke. I can still sew on it, but not well, and it's a total pain. I am dealing for now because I don't know what to buy to replace it, but it will need to be replaced eventually. Here's a sneak preview at what I need to do:
Non-disney...things I want to do before Sydney's surgery:
1. Make stuffed animal Pig for Syd, and Monkey for J.J.
2. Finish Syd's "S"...remember I posted about that way back at the beginning? Still not done. And I need to do it before summer is over because I don't want to use the spray paint in the house.
Disney:
1. Make shoes. 2 Halloween, 2 or 3 for Sydney (I don't remember how many fabrics I have.
2. Princess Tiana dress, 101 dalmations dress
3. Diapers (yeah...I decided I'd rather have pocket diapers instead of a two step system...the lure of something that was one piece that I could just put on really fast got to me. So I'm making fleece pocket diapers. I have 12 made, 8 to go. On my broken machine.)
4. ID for stroller...still working this out.
5. Make ADR's.
6. Make PJ's for the kids for the trip
7. The bow for Sydney's dinosaur costume
...
I know there's more. But that's some of it. It sounds like a lot in 10 weeks considering my machine is broken AND I only can do this stuff while the kids sleep (well, I'm sure I could do it while they're awake but I try not to). It would have been too much for 5 weeks!
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