The trip will have been extra special for Meghan though, as it's believed this was the first time she met Eugenie and Jack's new baby boy, Ernest.
Harry and Meghan stayed at Eugenie and Jack's home in the exclusive coastal town of Melides. Jack heads up the sales and marketing team at CostaTerra Golf and Ocean Club and the family are said to be living at a property on site.
The Sussexes will no doubt have spent plenty of time bonding with four-month-old baby Ernest and Ernest's older brother August, two.
Harry has been back to the UK since Ernest's arrival in May, most notably to give evidence in court in his phone-hacking case against Mirror Group Newspapers in June. So it's likely he will have already met baby Ernest as Eugenie, who is on maternity leave, divides her time between the UK and Portugal.
Harry and Meghan tagged on their Portugal holiday to the end of their trip to Germany where they attended the Invictus Games in Dusseldorf, which ended on 16 September.
According to Portuguese publication Nova Gente, the Sussexes flew to Lisbon and headed straight to Melides, where Jack and Eugenie live.
The couple stayed for four days before departing on a British Airways flight on 20 September bound for London Heathrow, before taking another flight to Los Angeles to be reunited with their children, Archie, four, and Lilibet, two. The Sussexes live in Montecito, about an hour and a half drive away from LA, and Eugenie has previously been out there to visit her cousin.
Where do Princess Eugenie and Jack Brooksbank live in Portugal?
Jack and Eugenie split their time between the UK and Portugal because of Jack's job at CostaTerra Golf and Ocean Club. The development currently has "40 premier estate homesites" according to their website, but upon completion the private, gated community will have "146 estate homesites, and more than 100 additional turnkey club residences, golf cottages, and luxury villas".
Jack, 37, took up his new job last year. The resort is owned by multimillionaire property tycoon Mike Meldman, who is one of the three founders of Casamigos tequila alongside George Clooney and Rande Gerber.
Jack previously worked as a brand ambassador for Casamigos tequila, so has a long history with Mike. He was brought on to work in marketing, sales and promotion of CostaTerra Golf and Ocean Club.
It certainly looks like the most idyllic place to raise two children. The region boasts pristine beaches where surfing, sailing, snorkeling, and paddleboarding are all to hand, as well as catamaran cruises to see dolphins. Horseback riding and hunting for wild boar and partridges are also among the more active outdoor pursuits on offer, as are hiking along the unspoiled trails.
The website goes on to describe CostaTerra as "authentic, unpretentious, and fun". Jack and Eugenie may have taken Harry and Meghan to some of the development's sociable gathering spots, like CasaNova, a shabby-chic beach restaurant that delivers toes-in-the-sand dining but also has a private lounge. Or they could have hung out at The Nest, a grown-up tree house hidden away in the pines with views of the golf course and ocean. A perfect spot for a sundowner.
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