For millions of animal-loving Brits, taking a pet abroad is easy these days - you just get them a passport.
But prior to February 2000, animals were quarantined for six months when returning to the UK from the Continent - thanks to a longstanding fear of rabies.
That was until Lady Mary Fretwell started the Passport for Pets pressure group and called for an end to quarantine laws.
Mary came up with the idea during her frequent trips back to the UK from France in the 1980s with her husband, the British diplomat Sir John Fretwell, and their dogs.
It was after one such trip in 1987 that their basset hound Bertie became ill while in the quarantine kennels, and died shortly after.
Heartbroken and fed up with poor animal welfare, Mary launched a campaign to end outdated quarantine laws, arguing that a passport scheme based on modern vaccines and blood tests was a better alternative.
An end to quarantine
She eventually won huge support across the UK and the pet passport launched in the UK on 28 February 2000 - allowing pet dogs, cats and ferrets from certain countries to enter the UK without quarantine.
As a result she was later awarded an OBE (Most Excellent Order of the British Empire) by the Queen in 2001 for her services to animal welfare and pet owners.
Speaking to the SUR in English from her Marbella home, Mary said that introducing the scheme felt "marvellous".
Mary, 79, said: "About eight of us went to France with our pets the day the law changed, we stayed in a hotel for the night and then came back on Eurostar with them. That was 19 years ago and three million cats and dogs have used the pet passport since then. The army use the service a lot as they use a lot of dogs, so that's no longer a problem for them.
"And it was all because of the modern vaccine that made it possible."
However she is worried for the future of pets travelling to and from the UK with a possible hard Brexit on the cards later this year.
Mary, who has recently got a French passport for her dog, explained: "If there's a hard Brexit the UK pet passport will become invalid. [People in Spain] should, and this is my advice, go to a Spanish vet and get a Spanish pet passport too, just in case.
"This is advice from the British government. It's just a sound insurance policy if you want to continue coming with your pet."
Brexit issues aside, Mary now plans to spend more time in Marbella, where she has owned a home since 2009.
But her Spanish connections run deeper. Born in 1939 in Falmouth to an English father and a Spanish mother, Mary explained that her parents married in Malaga Cathedral in 1936 during the Spanish Civil War.
She said: "My mum was called Isobel Toking, as her father was English, although he lived all of his life in Spain and spoke English with a Spanish accent. His grandfather came to Spain and founded the cable from Bilbao to Cornwall under the sea. He stayed with his English wife in Spain, had four boys, and one was the father of my mother.
"My mother did not speak English when she met my father. Growing up she tried to speak to me in Spanish, but my sister and I hated it because we were English and we pretended we were deaf, but she would persist, which helped a lot. My father spoke good Spanish too."
As for Mary, she grew up near Croydon and joined the Foreign Office at 18 as a shorthand typist.
She said: "It was a mistake, as I thought the whole idea was to go abroad and travel. But you couldn't go abroad until you were 21 in those days and so I stayed about a year. But that's where I met my husband, he was a career diplomat. He asked me to marry him and then we went off to Moscow for three years."
Mary and John Fretwell then spent a lifetime moving to British embassies around the world, including Washington, Poland, Paris and London.
Mary recalled: "He was quite a clever bloke from a mining town and went to a grammar school. He got a full scholarship to Cambridge at 16 and went after his military service.
"The Foreign Office was good in those days; they paid you to learn languages, so he learnt Mandarin. He was the brains, I was the peacock."
In 1982 Mary's husband, who died in March 2017, was knighted for his services to the country as a Senior British Diplomat, and Mary acquired the title of "Lady".
"It's not fair really, if women have done well in their jobs and are knighted as such, they are made a Dame, but it doesn't mean their husband is made a Sir," she added.
"It is quite good for getting into restaurants though."
Back to Spain
As for her love of Spain nowadays, she explained: "The weather is good, the humour is good, the food is good, it's all just very enjoyable.
"I remember coming to Fuengirola when I was seven, as my granny had a fisherman's cottage when it was just a fishing village. I spent six months with my mother and my sister in Fuengirola.
"At the time the goats would come to your door. It's massive how it's changed. The taxi was a horse and carriage driving to Malaga. I have very fond memories of that time and the joy my mother had and what she missed when she was in England."