Queen Sofia of Spain burst into tears during an event at a university in Madrid where she was present. The 84-year-old became emotional while praising a physics teacher who was named dean with whom she had been friends for years, according to local media reports.

A publication of the British Daily Mail attributes Sofia’s emotion to the fact that she has not been invited by her son, King Philip VI, to the swearing-in of his daughter, Princess Eleonora of Asturias, on Tuesday, October 31, the day on which she has her birthday and turns 18 years old.

The palace is reportedly trying to avoid a backlash over the controversial former king, who abdicated in favor of his son Felipe in 2014 and went into exile in Abu Dhabi.

Neither Juan Carlos nor Sofia will attend the public events tomorrow. Both are only set to attend private family celebrations after the event.

An official ceremony is planned for the 18-year-old princess’s birthday in the Spanish parliament during which she will pledge allegiance to the Constitution before receiving the congressional and senate medals.