Regarding the question of wills and siblings, I was very, very lucky.
My brother, sister and I went with my dad to an attorney before he became so disabled from Alzheimer and got the will written. My brother & sister asked that I be named power of attorney, because they believed that I would spend the most time looking after him. Every month I sent them a spreadsheet of expenses & balances so they knew exactly what was going on. When dad died, I took all that was remaining and divided it equally 3 ways. We were more interested in using Dad's money to care for him rather than being concerned about what was left for us. We were very grateful that he planned so well for the future. Even after he died, we each received a tidy sum, but if he had needed it all, it would have been fine with us. We are probably one of the few families who had no issues over money or anything else.