My 12 yo is very responsible. when she was 10 and I was expecting her baby sister she actually called the paramedics and saved our lives. My DH was out of town and I had a severe potassium imbalance (like Terri Schiavo had). Doctors when this was discovered said that baby and I would not have made it through the night. I didn't even realize I was sick..
We would love to take a few days alone but have not family to help.. thats why we were toying with the idea of having a quiet drink in the lounge for an hour..our private celebration so to speak... but with all of your input - I think we'll just get some vino and apps (dose both kids with dimetapp
) and hope for the best for our mini celebration in room/balacony.. thanks everyone.. 
We would love to take a few days alone but have not family to help.. thats why we were toying with the idea of having a quiet drink in the lounge for an hour..our private celebration so to speak... but with all of your input - I think we'll just get some vino and apps (dose both kids with dimetapp
) and hope for the best for our mini celebration in room/balacony.. thanks everyone.. 
I'm sure all the sitter's from those places are as awesome as everyone says, but we're too paranoid to use them with DS5, DD3 and DD 8 months. However, if there was a considerably older child in the mix, I'd feel much better about it. And that way you two could really relax and enjoy yourselves without worrying as much. You could still do the cell phone thing just to be safe.
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. This is what I suggested the OP do between now and her December trip.
I know this seems funny but honestly that's why I wouldn't do it at home.
Toddlers and babies are just totally unpredictable. On a recent disney trip, my dd2.5 blindly reached up on the table (she is very short), grabbed a full unopened can of diet pepsi and dropped it onto her big toe, breaking it. What a way to start a vacation. I watched the entire thing, too slow to grab her.