The love child of the former king of Belgium is seeking the same rights and titles as her father's legitimate children via the courts.
Delphine Boël, 52, is the child of the former Belgian King Albert II.
The ex-royal admitted he was her father in January of this year after he had fought the paternity claim for over a decade.
The mother of artist Delphine, Baroness Sybille de Selys Longchamps, claims that she had an affair with Albert, 86, before he became king.
Delphine Boël, the love child of the abdicated Belgian king, Albert II, who is asking the courts to grant her the same rights as his other children
The former Belgian King Albert II who is the father of the artist Delphine Boël
Rumours of a royal scandal first sprang up in 1999 due to claims of an illegitimate child in an unauthorised biography about Albert's wife, Queen Paola.
The former king had never made any public statement on the allegations, except for a cryptic statement in his 1999 Christmas message in which he said he and Queen Paola lived through a 'crisis' in the late 1960s that almost wrecked their marriage, but that 'a long while ago' they overcame their marital problems.
The BBC said that Miss Boël initially alleged on record that King Albert was her biological father in 2005 during an interview.
After that, she repeatedly stated that she was the King's daughter and used it as a theme in some of her professional artwork.
While Albert was on the throne, he could not be compelled to appear in court - limiting Miss Boël's chances of proving her case.
However, she began court proceedings in 2013 when he abdicated from the throne and lost his royal immunity.
Miss Boël's lawyer, Marc Uyttendaele, said on Thursday that she is seeking the same rights as Albert's three other children - Philippe, now King of Belgium, Prince Laurent and Princess Astrid.
Mr Uyttendaele told the BBC: 'Delphine's position isn't that she wants or doesn't want to be princess.
'She doesn't want to be a cut-price child, she wants to have exactly the same privileges, titles and capacities as her brothers and her sister.'
A previous lawyer said that Miss Boël was not motivated by money, since she was better off as a Boël - an family of industrialists worth around $1billion.
Delphine Boël (centre), the love child of Belgium's former king, is seeking the same rights as Albert II's other children
Baroness Sybille de Selys Longchamps, mother of Delphine Boël, with Baron Dieter von Malsen Ponickau
King Philippe of Belgium who followed his father onto the throne
Princess Astrid, daughter of the former king Albert II, and his youngest son Prince Laurent
He was born in 1934 as the second in line to the throne, the son of the wartime King Leopold III and Swedish princess Astrid.
Astrid died in a car crash when Albert was 15 months old, and Albert fled the country when it was occupied by the Nazis during World War II, eventually returning to Belgium in 1950.
In 1959 he married the Italian Donna Paola Ruffo di Calabria and the pair remain married to this day despite Albert's acknowledgement of marital difficulties between the two.
They have three children together: Philippe, Astrid and Laurent, and Albert finally admitted earlier this year that Delphine Boël is his biological daughter.
Albert ascended to