Answer:
According to Clause 1, Article 73 of the 2015 Civil Code, it is stipulated that:
“Article 73. Revocation of decision declaring death
1. When a person who has been declared dead returns or where there is reliable information that such person is still alive, at the request of such person or of a person with related rights and interests, a court shall issue a decision revoking the decision declaring that such person was dead.”
Based on the above provisions, your sister has the right to request the Court to issue a decision to annul the decision declaring your sister dead.
Simultaneously, pursuant to Clause 3, Article 73 of the 2015 Civil Code, it is stipulated that:
“3. A person who had been declared dead but who is still alive has the right to claim his or her property or the remaining property value from the persons who received his or her inheritance.
Where the heir of a person who a court had declared dead is aware that such person is still alive but intentionally concealed such information in order to enjoy an inheritance, the heir must return all of the property received, including any benefits and income derived, and if any loss or damage has been caused, the heir must also compensate.”
Thus, your sister has the right to request those who have received the inheritance to return the assets and property values that are still alive according to the provisions of law.