Ok, I went to WDW last Aug with my dd (then six), just eight months after she was diagnosed with Type 1 diabetes. I was very nervous, but really we didn't have any big problems. A few lows, but no major ones, no real highs either.
I highly recommend the page linked above by the Badshoes. Great info and they are entertaining too! Like they say, it's very important to test, test, test. That's my motto for dd at any time, but especially at WDW.
One thing that helped us which I'm afraid wouldn't work for you as it appears your dd is 10 was a stroller. At that age I probably wouldn't have bothered, but with the diabetes and dd's penchant for lows, I'm so glad we did. I think you guys will just have to make sure to take extra breaks etc.
DD is also not on a pump (Lantus and Novolog). I packed doubles/triples of everything we would need. I packed WAY too many snacks lol. But you never know. I brought two vials of each of her insulins. You can get a fridge at no cost at WDW resorts because of the need to refrigerate insulin. But mods and deluxes have them anyway. At values for medical reasons, they may only give you a teensy one, smaller even than dorm size. When you check in, check the setting of the refrigerator. I hear they often jack them up before people check in to make sure they are very cold. Unfortunately sometimes that results in people not noticing the temp and medications/food freezing. You don't want that to happen to the insulin!
Any way, I carried one vial of the Novolog with us throughout the day (in a Frio pack) and left the extra Novolog and both vials of Lantus in the fridge. I also had a huge fanny pack (yes, I looked like a pack mule lol) with the insulin (in Frio pack), meter kit, glucose tabs, cake gel, glucagon kit, syringes, glucose tabs and some fruit roll ups and crackers. I also had Lia wear her own mini fanny pack with another meter kit, glucagon kit, cake gel, glucose tabs and a fruit roll up. That way if she went with grandma or my sister on a ride without me, they were covered for an emergency. Of course she also wore her medical bracelet which has my cell phone number engraved, that way if she got lost, I told her to immediately go to a WDW CM and show them that. We wore our fanny packs on the rides, because me being a nervous nelly was just sure a ride would break down and we'd be stuck and Lia would go low. Well, you never know! Didn't happen though thankfully!
Honestly I was prepared for just about every scenario I think and it went very smoothly. Lia's ratio is still very low 1:60 so she's extremely sensitive to even the smallest amounts of insulin and it's hard to dose those miniscule amounts. So for her I found just dosing less or even none at all at meal times and then letting her have a slushie or ice cream bar uncovered, worked very well.
Heck, she probably had more junk food than she would have had without having diabetes! It's ironic. I very rarely let her have juice before, now since diagnosis, she gets lots of juice and fruit roll ups (NEVER had those before). Go figure...
Good luck. Just be prepared for everything, test, test, test and take extra breaks in the heat and it should go well.
