The Duke and Duchess of Cambridge begin their visit to Pakistan on Monday, with a source telling HELLO!: "It's their most challenging tour to date." William and Kate, both 37, are travelling without their children Prince George, six, Princess Charlotte, four, and one-year-old Prince Louis, who will remain in London.
George and Charlotte are in the middle of their school term at Thomas's Battersea and given the complexity of the Pakistan visit, the security considerations are much greater, so it makes sense that they aren't accompanying their parents. They have previously joined William and Kate on their tour of Germany and Poland in 2017 and Canada in 2016, but Louis is yet to make his debut overseas.
So, who will be looking after the Cambridge children while William and Kate are away? It's likely that their nanny Maria Teresa Turrion Borrallo will be on hand to do the school run and take care of their evening routines. Spanish-born Maria is a Norland-trained nanny and has been working for the Cambridges full-time since 2014 when George was eight months old. She's been spotted in her distinctive brown uniform on previous royal tours and during official family events.
READ: Prince William and Kate Middleton are en route to Pakistan - details
Maria in her uniform at Princess Charlotte's christening in 2015
Norland nannies are trained in everything related to child rearing, from cooking to first aid, but in Maria's case, the Spaniard will have specialist training in security and defensive driving.
It's also likely that Kate's mother Carole Middleton, 64, will be on baby-sitting duties for her grandchildren. Carole and husband Michael, 70, are said to have a very close relationship with George, Charlotte and Louis and were spotted looking after them while William and Kate competed in the King's Cup regatta this summer.
Carole with Kate and Charlotte at the King's Cup regatta
In an interview with The Telegraph last December, businesswoman Carole said that she loves the festive time of year so much that she has as many trees in her house as possible, including in the grandchildrens' rooms: "so that they can decorate it themselves." Michael and Carole also became grandparents for a fourth time last October when their youngest daughter Pippa gave birth to her and James Matthews' first child Arthur.
MORE: Why the Queen didn't wear the Imperial State Crown at the State Opening of Parliament
The Duke and Duchess of Cambridge will return home to their children on Friday 18 October.
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