woofgang, as I said I am no authority so you may be right. However to me he sold his quarter share, but then may have gained a ninth share, being a third of his sister's share, when his sister died, depending on the type of agreement they had. If they had a tenants in common agreement then the sister's share of the house was just part of her estate and her brother would be entitled to his share assuming there wasn't a spouse or children. If they had a joint tenant agreement there could be no such claim.