No, sis, your brat is NOT entitled to HIS family's estate
My sister was a single mother. She was fortunate, hot and young enough to be able to marry an older wealthy man whose first wife had passed away from cancer. My brother-in-law had recently passed away. He left a little bit of money only for my sister, not a lot but enough for her to take care of herself and her child. However, he did not leave anything specifically for her (not his) child. He had never formally adopt her child. In his will he left almost all of his estate to his own biological children whom he had with his first wife.
My sister is bitter. She thinks her (not his) child deserves some of his estate. She wants to fight his will, and she has turned to me for support.
My truth is... I disagree with my sister. I agree with my brother-in-law's will. First of all, most of his estate had been passed down through generations and his family line, from his grandfather to his father to him (and now to his biological children.) Obviously he had diversified, expanded and and increased his family's wealth, but all of it was still based on what his forefathers had built. His estate is technically still his hereditary family, not just his. My nephew is not biologically related to my brother-in-law. He is not part of his family bloodline. I really do not see why my nephew should receive any of the estate or money that is passed down through my brother-in-law's bloodline when my nephew is not a part of that bloodline.
However, I have decided to just listen and not tell my sister of how I really think because she is not gonna react well. She is gonna act hysterical and unreasonable. IMO she should just be thankful that she got anything at all.