In the Dutch constitutional system no one may sign Acts of Parliament or Royal Decrees on behalf of the Queen. Even when the Queen is ill or is abroad on holiday or state visits, urgent documents are presented to her for signature. Only if the monarch is unable to exercise the royal prerogative owing to serious health or other problems could Parliament appoint a Regent to exercise the prerogative on her behalf. This procedure, which is laid down in Article 37 of the Constitution, was last followed in 1948, when Princess Juliana temporarily assumed the duties of her mother Queen Wilhelmina. Until such time as a Regent has been appointed, the Council of State exercises the royal prerogative (Article 38 of the Constitution). This last occurred in 1889.