Day out with doting grandfather Henrik for Isabella and Christian

was every inch the doting grandfather as he spent the day with some of his eldest grandchildren in Denmark.

's husband kept a watchful eye on

s children

and

, and Prince Felix,

's son, at the Hubertus hunt. The group were spotted watching from a balcony of Eremitage Palace as the annual event – a imaginary fox chase which takes place every autumn in Klampenborg, north of Copenhagen – unfolded.

The foursome checked out the smartly dressed riders, and were on hand afterwards to help congratulate the winning huntsmen. Watching the family scene, it was easy to see how close Felix – younger son of Joachim and his first wife Alexandra, Countess of Frederiksborg – is to his cousins. The ten-year-old spent the day laughing and playing with Christian and Isabella – who is known as Bella to her family. The little girl – who has inherited her mother

's delicate features and her father's blue eyes – hardly stopped smiling for a moment. Royal watchers were wondering if Isabella and Christian's little siblings

and

will attend next year. By the next time the hunt takes place, the twins will be almost three – the age their big sister was when she made her debut at the event.

Isabella first

, accompanied by her big brother and her maternal grandfather John Donaldson, who was looking after the two while their parents accompanied Prince Henrik on an emotional return to his former home in Vietnam. Back then she was almost the same height as her older brother, but these days Christian is almost a head taller than his five-year-old sister. Christian

, and shows more of his emerging personality with each passing year. At the

Olympics this summer, the little boy had Danish officials in stitches when he

while the cameras were trained on him. Isabella is also known for her playful nature. At the hunt

, the little girl couldn't resist pulling faces at photographers.