Sienna Miller at ATG Summer Party at Kensington Palace in London, September 6, 2021

Sienna Miller at ATG Summer Party at Kensington Palace in London, September 6, 2021 - 1

Sienna Miller at ATG Summer Party at Kensington Palace in London, September 6, 2021 - 2

Sienna Miller at ATG Summer Party at Kensington Palace in London, September 6, 2021 - 3

Sienna Miller at ATG Summer Party at Kensington Palace in London, September 6, 2021 - 4

Sienna Miller at ATG Summer Party at Kensington Palace in London, September 6, 2021 - 5

Sienna Miller at ATG Summer Party at Kensington Palace in London, September 6, 2021 - 6

Sienna Miller at ATG Summer Party at Kensington Palace in London, September 6, 2021 - 7

Sienna Miller at ATG Summer Party at Kensington Palace in London, September 6, 2021 - 8

Sienna Miller at ATG Summer Party at Kensington Palace in London, September 6, 2021 - 9