French first lady Brigitte Macron has been mourning the death of her beloved sister during her state visit to Britain.

Her apparent aloof manner had been picked up on as she accompanied President Emmanuel Macron, 47, to the UK this week. It didn't go unnoticed that, as the world leader descended the steps after their plane landed, he reached out a helping hand to Brigitte, 72, who appeared to snub the supportive gesture in favour of gripping the handrail.

Ms Macron's sister Anne-Marie Trogneux died last week, but she refused to let her husband travel to London alone. The couple have been married for 18 years, and she was his drama teacher in high school.

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Her sister Anne-Marie died at the family's home town of Amiens, northern France, last Tuesday. She is the second sibling Ms Macron has lost after a car crash killed Maryvonne Trogneux when she was just 27.

"This is the main reason Ms Macron has been looking so subdued and uncomfortable with her husband, a source close to the couple told us today. Madame Macron adored her sister, and the loss has affected her greatly," a source told MailOnline. "But she agreed that it was her duty to be in the United Kingdom, despite it coinciding with a period of mourning."

In May the couple brushed off an incident that appeared to show the French President being slapped during a heated exchange between them. The pair, who were on a tour of Southeast Asia at the time, were filmed arriving at Hanoi airport in Vietnam on their official plane.

A shocking clip shows Macron's profile through the vehicle door. Seconds later, his wife quickly raises a hand to his face and appears to strike him. The president can be seen looking taken aback, before he addresses onlookers by waving and smiling at them outside.

The two then walk down the stairs, with Mr Macron attempting to hold her hand, but she chooses not to take it. Instead, the First Lady holds onto the handrail of the walkway. An Elysee official denied it showed an argument between the couple, with a statement saying: "It was a moment when the president and his wife were relaxing one last time before the start of the trip by having a laugh."

The French President was just 16 when he vowed to marry Trogneux - a married mum-of-three at the time - and his parents even tried to put a stop to the schoolboy love affair, according to a book. The unusual love story has captivated French tabloids and magazines, and emerged as a major storyline during Macron's rapid rise towards the Palace, with both the husband and wife hitting back at critics. Mr Macron, who was elected in 2017 as the Republic's 5th youngest ever president, has repeatedly paid tribute to his wife and her unwavering support.

During their visit, Mr Macron blew the Kingand Queena kiss as he said an official farewell to them outside Windsor Castle. The President and his wife showered the Royal family with thanks for their welcome to Windsor Castle, as he repeated the King's new phrase of "Entente Amicale" in celebration as they left.