Halálának
Halálának is a Hungarian grammatical form derived from the noun halál (death). It combines the base with possessive and inflectional suffixes to express “of his/her/its death” or, depending on context, “the death of someone/something.” In practice, halálának is used to link death to a specific possessor in a genitive-like construction.
In usage, halálának appears in formal or written Hungarian, such as obituaries, historical accounts, medical or
Halálának contrasts with halála, which also means “his/her death” but is a simpler, often less possessive form
In short, halálának is the standard genitive/possessive form for discussing “the death of” a particular person