Queen Sofía of Spain appears unsteady at military event in Madrid

Queen Sofía of Spain appeared unsteady on her feet on Monday as she attended a military event in Madrid.

The 85-year-old royal, who was Queen of Spain as the wife of King Juan Carlos I until he abdicated on June 19, 2014, was climbing a step in high heels when she faltered and put her arms out in an attempt to steady herself. 

She was quickly assisted by an aide and was able to regain her composure.  

The mother of King Felipe VI of Spain, who has previously been spotted in a wheelchair on occasion at royal events, was in Torrejón de Ardoz in the Spanish capital to commemorate the 19th anniversary of the creation of the Military Emergency Unit.

The Military Emergency Unit is part of the Spanish armed forces and is responsible for providing disaster relief throughout the country and also abroad when necessary.

Sofía, who was rushed to hospital in April for a urinary tract infection, was helped by an aid who held out his arms to break a potential fall. 

Apart from this episode, the former Queen - who reigned for almost four decades alongside her husband from November 1975 - was composed as she received the military salute at the Torrejón Air Base.

Smiling as she posed next to a plaque commemorating the anniversary of the Military Emergency Unit, which was established on October 7, 2005, she appeared in good spirits. 

The royal, who will turn 86 at the beginning of November, looked elegant in a formal black trouser suit adorned with a gold and blue brooch. 

She paired the collarless jacket, which was embroidered with a crisscross pattern and embellished with a beaded trim, with matching wide-leg trousers. 

Sofía's accessories included black, round-toe heels, a miniature black handbag and a number of gold and jewelled bracelets. 

She wore her light brown hair in a blow-dry and kept her make-up simple for the occasion.  

Sofía, who generally enjoys good health, stays active by using a walking machine in her room in the Zarzuela Palace on a daily basis. 

When she was hospitalised on April 11 with a urinary tract infection, it was her first hospital stay since she gave birth to King Felipe in 1968.

Born Princess Sophia of Greece and Denmark on November 2, 1938, at Tatoi Palace in Athens, Greece, she is the eldest daughter of King Paul of Greece and Frederica of Hanover.

A member of the Greek branch of the Schleswig-Holstein-Sonderburg-Glücksburg dynasty, her great-great-grandmother was Queen Victoria.

As such, she was both a relative and a friend of the late Queen Elizabeth II and Prince Philip.

Because Sofía's family were forced into exile during the Second World War, she spent part of her childhood in Egypt and South Africa.

She finished her education at the prestigious Schloss Salem boarding school in Southern Germany, and then studied childcare, music and archaeology in Athens.

Sofía also studied at Fitzwilliam College, a constituent college of the University of Cambridge.

A keen yachtswoman, the royal represented her home country of Greece as a reserve member of the Gold Medal-winning sailing team at the 1960 Summer Olympics alongside her brother Constantine (heir to the now deposed Greek monarchy).

Sofía met Infante Juan Carlos, her paternal third cousin, in 1954 while on a cruise in the Greek Islands and again at the Duke of Kent's wedding in 1961.

They married less than a year later in Athens at the Catholic Cathedral of Saint Dionysius.

Upon their marriage, she converted from Greek Orthodoxy to Catholicism and changed her name from Sophia to Sofía.

Soon after, in 1973, the monarchy in Greece was abolished.

Together, she and Juan Carlos have three children: Infanta Elena, Infanta Cristina, and King Felipe.

Juan Carlos is judged to have been instrumental in Spain's peaceful transition to a democracy and, with his wife Queen Sofía, they enjoyed popularity at home. 

The couple had a close relationship with Queen Elizabeth and the British Royal Family - Prince Charles, Princess Diana and their two sons William and Harry would often spend holidays at the summer palace in Majorca.

As well as accompanying her husband on official visits, Sofía also undertook solo engagements.

She remains executive president of the Queen Sofía Foundation and is honorary president of the Royal Board on Education and Care of Handicapped Persons of Spain, as well as the Spanish Foundation for Aid for Drug Addicts.

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