Known for being a bit of a cheeky child, it comes as no surprise that Prince Harry pulled the hilarious stunt on the balcony - and it seems his cousin Savannah has inherited his sense of humour.
Like their younger brother, Prince George and Princess Charlotte were both showed to the world on the Lindo Wing steps of St. Mary's hospital shortly after their births and were both not seen again until their Christenings.
The adorable three-year-old was standing in front of her mother, Kate Middleton, when she could be seen glancing over at the Monarch.
At Prince Harry's wedding, it was Princess Charlotte who appeared to be the most mischievous as she re-enacted her uncle's cheeky tongue-out pose in the vehicle as she left St George's Chapel.
Some viewers say that the young princess might have hit her head on the railing.
Princess Charlotte certainly enjoyed an action-packed couple of days this weekend.
In April, she charmed fans when she accompanied her father and brother to the Lindo Wing to meet Prince Louis for the first time and began waving as soon as she stepped out of the family vehicle. The Queen also chuckled when she saw little Charlotte practising her royal wave and exchanged a few amused words with Kate about the youngster's antics.
Her mum, the Duchess of Cambridge, who often likes to coordinate Charlotte's outfits with hers, was also wearing a summery frock.
But apart from her little fall, it's her wave that we can't get enough of.