In the event that a person has died without having made a will, the heirs have to initiate the procedures to be able to inherit according to the law, specifically as provided in the Civil Code. It would be necessary to formalize before a notary what is called "declaration of heirs", which will be included in a notarial deed, in which it will be defined who are the relatives with the right to inheritance. To do this, a series of documents must be taken to the notary (DNI of the deceased; death certificate; certificate of the Registry of Last Will Acts; Family Book...) and two witnesses who know the family of the deceased must attend. . If they are relatives, they cannot have a direct interest in the declaration. The notary can ask for any additional evidence he needs. The declaration of heirs is more complex and expensive than a will.
It is not necessary for all the heirs to sign, but rather any of them, that is, the widower, one or more children, can request before a Notary Public the declaration of heirs, which replaces the lack of will. Subsequently, the procedures for acceptance and adjudication can be initiated.