Fergie captioned, 'Thank you Teddy M for working on this amazing painting for @childrenincrisis and congratulations on creating one of @teddysphotos art guitars #art #music'
However, the behaviour of Fergie, Beatrice and Eugenie might fly with Her Majesty, as it's all in the name of a good cause.
The original painting, dubbed 'Royal Love', was created in 2016 by GQ Magazine, with the artist stating: 'We painted outdoors on the lawn, kneeling over the artwork and it was such a relaxed experience.
'When you look at the painting, you will see three distinct forms of handwriting. Beatrice on the bottom left, Eugenie bottom right and the Duchess across the top.'
Adding: 'And the name of the painting, 'Royal Love' seemed obvious to me and the Duchess quickly approved.'
The painting was auctioned at the Masterpiece Fair in 2016, and sold for £15,000 (AU$27,000), with all the money going to the charity, Children in Crisis.
Recently, Teddy M has teamed up with Ed Sheeran for fundraising efforts, with his art guitars raising thousands of dollars for a number of charities.
