Aside from being told this by an actual estate attorney (the discussion was about how to make provisions for a child not born yet, and in that conversation she said you can legally disinherit a child, but you had to do it explicitly, or it would be assumed you just accidentally omitted the kid and he would get a share). Not having the time to dig through Google for a cite that would be acceptable, I offer this and this as the best I can do. I’m talking about NY. I’m pretty sure other states are different. A lawyer could do better at explaining this.