I'm sorry you have so much to face with this surgery. My daughter was 9 when I had my fusion and she had a very hard time with it. The most serious problem (other than the hospital stay and her fear about mama) was my pain when I came home. She was very upset that she couldn't hug me or lay with me for quite a while. I wish I had explained this to her upfront, but I did not know I would be having surgery when I went to the Dr that morning. She had no way of knowing what to expect.
Even though you are working with a younger child, it will be very important to explain how much you love them and would love to hug them and lay with them, but that the Dr says you must be sure to stay still and quiet until your body gets well. Perhaps a new special bear or doll would be appropriate to "hold" your hugs until you can give them again. Also, I'd make sure that your child was aware that you may cry or need a lot of help for a while even for going to he bathroom. It's so hard for them to see mama in pain. Lastly, I'd make for sure and certain that your child is aware that there will be medications (perhaps patches) around and that they are never, ever to touch a medicine. Some of our meds are so strong that they could have horrible ramifications if they are even touched by your child.
I know I'm probably telling you things you already know, but it's so hard to remember things when they are facing you. I hope everything goes perfectly and that you and your family have a speedy recovery and a very successful surgery experience.
Failed fusion L5-S1, Pituatary damage, HGH Def, Fibro, Bladder surgery failure, Nissen Failure, GERD, OCPD, GAD, MDD, CTS (Bilateral Surgery completed), CFS, TMJ, Migraines, Vit D, A, Magnesium deficiency, Pre-glaucomic (sp?), HBP, Idiopatic Reactive Hypoglycemia, Edema, too many Drug/Food allergies, sensitivites, and current meds to list.