The King shares three children with Queen Silvia, including Crown Princess Victoria, Prince Carl Philip and Princess Madeleine.
Their children have collectively provided them with a total of seven grandchildren (all with royal titles and dukedoms).
According to Express, King Carl XVI Gustaf has decided to reduce the number of people in The Royal House to "establish which members of The Royal Family may be expected to perform official duties."
The official statement from Fredrik Wersäll, the Marshal of the Realm, said: “His Majesty The King has decided on changes to the Royal House.
“The purpose of these changes is to establish which members of The Royal Family may be expected to perform official duties incumbent on the Head of State or related to the function of the Head of State.
“His Majesty The King has decided that the children of Their Royal Highnesses Prince Carl Philip and Princess Sofia, and the children of Her Royal Highness Princess Madeleine and Mr Christopher O’Neill will no longer be members of The Royal House.”
The change means that five royal family members will lose their titles of Royal Highness but will retain their title of Duke or Duchess.
Princess Madeleine of Sweden and Prince Carl Phillip of Sweden will continue their work with charities and perform official duties for the King and Queen of Sweden.
Prince Carl Philip and his wife Princess Sofia have been together since 2015 and share Prince Alexander, Duke of Södermanland, born in 2016, and Prince Gabriel, Duke of Dalarna, born in 2017.
Both Madeleine and Carl Philip will reportedly continue their work with charities and perform official duties for the King and Queen.
What's more, Princess Madeleine is a published author - she recently released a children’s book “Stella och hemligheten” (Stella and the Secret).
The Swedish royal plans to give 100 per cent of the revenues from the sales of her book to the Foundation.
Princess Madeleine (The youngest daughter of King Carl Gustaf and Queen Silvia) married British-American financier Christopher O’Neill in 2013.
Their children include Princess Leonore, Duchess of Gotland, born in 2014, four-year-old Prince Nicolas, Duke of Ångermanland, Princess Adrienne, Duchess of Blekinge, born last year.
King Carl XVI Gustaf of Sweden has sensationally removed several members from the Royal House.
The Heir Apparent of Sweden is Crown Princess Victoria.
Her children, Princess Estelle and Prince Oscar are the only grandchildren remaining part of his Royal House as second and third in line to the throne.