Wills and Estates

Do I need a will or living will at 56 years old?
I am 56yrs currently healthy with adult children. I'm divorced, what do I need a will or living will? What is the difference?
Can my mom add a stipulation to her will with a handwritten note?
I've got a question to ask for my mom. It's regarding an inclusion she wants to add to their will. Both parents are living and a will was written a few years back with an attorney. Mom wants to make a stipulation that when they both pass, after the sale of their home, that a certain dollar amount should first go to my oldest son and his brother to be used solely for the purpose of helping pay off incurred student loans or if applicable,current college costs. One of my sisters once told her that she can write this information on a piece of paper and have 2 people that are not included in the will to sign it, hence acting as witnesses. She plans on putting the paper in the 'box' along with their will. Will this hold up legally if it were disputed by any one of my 3 sisters? Myself and their 3 additional daughters are sole heirs.
Can my mother sign a transfer on death (TOD) form to eliminate probate?
My mom is dying. She survives my Dad. She has some personal assets which are in her name. She has a will that dispenses monies from $1000 to $25000 to various people and leaves the remainder to myself and my brother. The total assets are less than then amount that would trigger estate tax. Should I have her sign a transfer on death (TOD) form to eliminate probate. If so, how to fund the people in will to avoid any tax (such as gift tax) ?
Can I access my uncle's money due to financial hardship?
If I am about to lose my home and I have a very wealthy uncle (That has my fathers stock 22 million) is there such thing as a hardship where I could get the money from him through a lawyer? He wont talk to me because he took my fathers stock when he was dying and heavily medicated. This was to be mine and my sisters money when he passed, so, my uncle wont speak to us because he knows what he did and doesn't want to have to answer for it. He lives in California. I live in Washington state. I was on disability for years and when I inherited a small amount of money so they cut me off and said I owe them 20,000. The money I inherited wasn't spent foolishly; I put money down on a home. I don't have any work skills and I am disabled and I am afraid I will lose my home because this is the last month I am able to pay my mortgage and other bills.
Do I need to update my will if my address and phone number have changed?
If a will was made twenty one years ago and the addresses and phone numbers have changed, do they need to be changed to be legally viable?