"Fall heir to" typically means to inherit something, but there are a number of antonyms that convey the opposite meaning. Instead of something being handed down or passed on, these words and phrases suggest a loss or absence of inheritance. Antonyms might include "dispossessed," "deprived," "bereft," "defrauded," "robbed," or "bankrupt." Depending on the context, synonyms like "earn," "acquire," or "purchase" might be more appropriate. Regardless, antonyms remind us that things are not always as they seem, and that there are always multiple perspectives and interpretations of a given situation.