stepped out for her third Buckingham Palace garden party of the season and she chose quite the avant-garde hat. The Princess Royal, 73, opted for a tailored longline coat in a pale grey fabric with subtle floral patterning. The knee-skimming garment featured a sharp collared neckline and faux pockets for added interest.

The Princess has been known to wear these smart coat dresses for formal occasions for a put-together look, even on warmer days. It wouldn't be a royal garden party look if it didn't feature some kind of eye-catching headwear. The Princess didn't disappoint, opting for a hair-heightening grey number with cornflower blue satin trim and a large flower adornment made from feathers.

s mother opted for a classic set of accessories, opting for a double string of pearls, a pair of navy gloves, and a crossbody bag slung over one shoulder. Her hair and makeup were similarly pared-back, as per her signature muted style, bar a shiny pink lipstick. Rounding off Princess Anne's look was a sweet seahorse-shaped gold brooch pinned to her left lapel.

The piece has remained a staple in her wardrobe and has been seen as part of a Princess Anne ensemble as early as 1979 when the royal attended the Great Children's Party in Hyde Park. It has been reported that the brooch was given to 's aunt on her wedding day to her first husband Mark Phillips in 1973 from the Fishmongers, the 4th of the medieval guilds of London. The garden party at Buckingham Palace, which was also attended by .