The death of 33-year-old Ines Zorreguieta was confirmed by Trudy Hulscher of the royal house's communications department.
Zorreguieta was a psychologist who worked for an office on social policies at the president's office.
Queen Maxima of Holland's youngest sister, Inés Zorreguieta, was found dead in Argentina in an apparent suicide, local media reported. Also shown in this family picture taken on the baptism of Princess Ariane in 2007 are (front row) Queen Maxima with Princess Ariane on her lap, King Willem-Alexander (centre right), and their daughters Princess of Orange Catharina-Amalia (left) and Princess Alexia (right).
Máxima said in a reaction that she is "very shocked and very upset" by the news, the RVD said.
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Further, struggles to pay a £4.2m tax bill owed to HM Revenue & Customs have left fans feeling a bit blue about things. The cash-strapped midlands club are determined they will not be held to ransom, Press Association Sport understands.
Inés Zorreguieta was found dead in her apartment in Buenos Aires yesterday night.
Zorreguieta and the Queen had a close relationship, as Zorreguieta was a bridesmaid at her older sister's 2002 wedding to then Dutch Crown Prince Willem-Alexander. Reports of her receiving medical treatment for problems with her diet and depression began circulating when she returned to the country. Her death comes 10 months after the death of Maxima's father Jorge Zorreguieta, who died at the age of 89 from cancer.
If you or someone you know needs help, please call the National Suicide Prevention Lifeline at 1-800-273-TALK (8255).