My mother had a daughter before her marriage to my dad (I’m the only full blood sibling of the marriage). My half sister has put forward that she wants 50% of my parents assests. She didn’t have the best childhood. My folks want us to negotiate together what we want in their wills before they draw them up. Currently She has a much higher amount of capital than me. I feel awkward asking for a higher percentage of their assets. They have quite a lot of assets between them. What would you do?