Grace’s home was built by her father, the son of Irish immigrants, in 1929. She was one of four and had two older siblings, Margaret and John, and a younger sister, Elizabeth. They grew up in a large house in small, close-knit Catholic community in Philadelphia.
Pictures of Grace’s childhood home show a large, red-brick house with a wide, white porch surrounding a black door.
There are many windows on the front of the house, all made up of small squares in white frames, complete with black shutters.
The house – both outside and inside – has been restored in recent years to look exactly how it did when Grace was a child.
There are images of her with her parents in their living room when she was just 26 years old, in 1956, showing them the new engagement ring given to her days prior by Prince Rainier.
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The interiors expert went on to explain that the house’s design is “very 1930s” and would have “definitely been on trend” during that decade.
She continued: “The maximalism is therein featured items such as the dramatic wallpaper and also the statement furniture. Something that people still want to this day.
“There is almost a cottage feel to the decor of that era and that is what makes it feel so inviting.
“The wooden floors and chairs combined with the statement floral and maximal upholstery and wallpaper creates a sense of a place that was cherished and would make you feel at home if you walked in – like as soon as you stepped foot in the door there would be an inviting presence and maybe even a drink, or two.
Ryan McDonough, interior design expert at MyJobQuote, added that Grace’s childhood home “is somewhat typical of upper-class America”.
“It has an overwhelming colonial style with shuttered windows, polished wood furniture, panelling and candelabra light fittings,” he said.
“It greatly reflects her family’s rich mix of American and European heritage and their high social standing. But there are also less formal touches with hints of mid-century design that was extremely popular in the 1950s.
“This can be seen in the home bar, comfy sofas and sprinkling of modern decorative objects.”
In 1956, Grace moved from the US to live permanently in the Palace of Monaco in the Monegasque principality. When she settled into her new home, was she influenced at all by the American-style interiors she grew up with?
Ryan told Express.co.uk: “An icon of style and glamour, Grace seemed to fit right in with the palatial interiors of her Monaco home, however she did bring some modern American style to the palace.
“American interior design at the time married Scandinavian-style clean lines with homely comforts and, although it was contained to areas of the home designed for family living, minimalist pendant lighting, modernist sofas and bright colours can be seen in small doses.
“This is undoubtedly Grace’s touch.”
The interior design expert added: “In the places where Grace influenced the design, such as the family room, there’s a less formal style with homely furnishings, yet it’s still very sophisticated.
“Away from the white, yellow and gold colour scheme that dominates many palace rooms, there’s a warmer palette too. And even more so than her old family home, there’s a mix of traditional and mid-century designer furnishings.”