Thailand’s Princess Bajrakitiyabha, who had been in a coma for more than three years, has died at the age of 47, the royal household has announced.

According to the BBC, the princess collapsed in December 2022 while exercising her dogs. At the time, doctors for the princess attributed the incident to a severe cardiac arrhythmia caused by a mycoplasma infection in her heart.

Her death deprives Thailand’s royal family of one of its most accomplished and prominent members, and a figure who many believed could have played an important role in the kingdom’s unresolved succession.

Born on December 7,1978, Princess Bajrakitiyabha was the eldest of King Vajiralongkorn’s seven children. Her mother is the King’s first wife, Princess Soamsawali.

The palace in Bangkok said in a statement on June 12 that the princess she died at 19:48 local time the previous evening at Chulalongkorn Hospital in Bangkok.

Trained as a lawyer, she earned two postgraduate degrees from Cornell University in the US and briefly served at Thailand’s mission to the United Nations in New York before returning home to work in the Attorney-General’s offices in Bangkok and elsewhere in the country.

From 2012 to 2014, she served as Thailand’s ambassador to Austria, and later became a vocal advocate of penal reform, focusing particularly on vulnerable women in prison; Thailand having one of the world’s highest numbers of female inmates.

In 2021, King Vajiralongkorn appointed her chief of staff in his private bodyguard unit, granting her the rank of general.

In her private life she was also known as a fitness enthusiast and regularly took part in long-distance running events.