heir presumptive

An heir presumptive is the person entitled to inherit a throne, peerage, or other hereditary honour, but whose position can be displaced by the birth of a person with a better claim to the position in question. This is in contrast to heirs apparent, whose claim on the position cannot be displaced in this manner. Overview Depending on the rules of the monarchy, the heir presumptive might be the daughter of a monarch if males take preference over females and the monarch has no sons, or the senior member of a collateral line if the monarch is childless or the monarch's direct descendants cannot inherit either because they are daughters and females are completely barred from inheriting the monarch's children are illegitimate, or some other legal disqualification, such as being descended from the monarch through a morganatic line or the descendant's refusal or inability to adopt a religion the monarch is required to profess. The subsequent birth of a legitimate child to the monarch may displace the former heir presumptive by creating an heir apparent or a more eligible heir presumptive. It is not assumed that the monarch and his or her consort are incapable of having further children; on the day before Queen Elizabeth II ascended the throne, her father George VI was gravely ill and her mother was 51 years old, but Elizabeth was still considered the heir presumptive rather than the heir apparent. An heir presumptive's position may not even be secure after they ascend their throne, as a posthumous child of the previous monarch could have a superseding claim. Following the death of William IV in 1837, he was succeeded by his niece Queen Victoria, whose accession proclamation noted her accession was only permanent so long as a child of William was not born in the following months to his widow, Adelaide, even though Adelaide was 44 years old and had last been pregnant 17 years earlier. Such a situation occurred in Spain in 1885, when King Alfonso XII died and left behind a widow who was three months pregnant. His five-year-old daughter and heir presumptive, María de las Mercedes, was not declared queen because she would be displaced if a son was born, and instead there was a six-month interregnum until the birth of her brother Alfonso XIII, who assumed the throne as king immediately upon birth.