Daintree I'm sorry the news isn't better . Sounds like Annabelle will be up for the same surgery/ies that my son had.
I too had another little one to look after. DH and I took it in turns to be at the hospital with our son - I'd go early in the morning and stay till after lunch, then he'd travel down to the hospital later in the afternoon and stay until around 9pm.
We made sure we still did some of the "regular" things with our daughter, like going for a walk, a swim etc.
Christmas day was very hard, and I don't think there's any way to really "prepare" for that. Just know that the NICU/SCU staff are very attentive and decorate the spaces with Christmassy stuff. We went in and saw our baby early on Christmas day, and then took DD to a family Christmas gathering for lunch.
My parents lived about 40 mins away, and would come and entertain DD once a week so DH and I could spend time together with our son at the hospital - so if you have someone around that your DD will stay with, that will be a great help when the time comes.
The other incredibly handy thing was that people from our church cooked for us during that time, did our gardening and even drove us the 50 mins to the hospital and back when they saw we were wrecked. If you have a support network, don't be afraid to accept whatever help is offered - it will benefit you, DH, your DD and your bubba.
If you need any more specific info about what to expect, drop me a PM
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