BANGKOK (Reuters) - Thailand’s 86-year-old Queen Mother Sirikit is being treated for a fever at a Bangkok hospital, the Royal Household Bureau said in a statement on Wednesday.

Sirikit, who was queen consort to the late King Bhumibol Adulyadej, who died in 2016 after seven decades on the throne, is mother to the current King Maha Vajiralongkorn, 66.

The queen has seldom been seen in public but last year the palace released photographs of Sirikit to mark her 86th birthday on Aug. 12. The queen was pictured with several of her children, including King Vajiralongkorn.

Sirikit was admitted to Bangkok’s Chulalongkorn Hospital on Tuesday after developing the fever caused by a bladder infection, the bureau said.

Many national holidays in Thailand revolve around the royals. Sirikit’s birthday is also celebrated at Mother’s Day.