This is something the Queen may enjoy and she appears to respond to Zara with genuine happiness.
Judi explained: “Zara’s body language looks more like that of a happy, playful child here as she leans back with both hands on the balcony in front of her.
“This, and the very affectionate-looking smile she aims at her grandmother, look like an invitation to share the fun.
“The Queen reciprocates, with a broad, eye-wrinkling smile that involves an upper and lower teeth display.”
The expert stated Zara takes on a “childlike” body language when with her grandmother which the Queen seemingly enjoys.
source: express.co.uk