A new photograph of Prince Louis taken by his mother has been released to mark his sixth birthday.
Catherine, the Princess of Wales, is receiving treatment after a cancer diagnosis.
After the controversy over changes to a Mother's Day family photograph, Kensington Palace has assured that this picture has not been edited.
The Prince and Princess of Wales are grateful for birthday messages for their son, says a palace spokesman.
With calls for Catherine to be given privacy while she has cancer treatment, the palace says it was aware of the difficult balance in then releasing a birthday photo of Louis, but decided to put out the picture as a way of thanking those who had sent birthday wishes.
The photograph of Louis, who is fourth in line to the throne, was taken in Windsor in the "last few days" says the palace.
The smiling picture of the schoolboy prince was published on social media with the message: "Happy 6th Birthday, Prince Louis! Thank you for all the kind wishes today."
This has been an "unprecedented time" for the Prince and Princess of Wales and their young family, says the palace, as Catherine continues her recovery.
In January she had abdominal surgery and subsequent tests had resulted in a cancer diagnosis, with treatment beginning in late February.
A family photograph taken by the princess for Mother's Day in March ended in controversy as photo agencies withdrew the picture over concerns that it had been digitally manipulated.
That fed a frenzy of social media conspiracy theories - and when Catherine released a video statement revealing her cancer diagnosis, it was recorded independently by OceanNewsUK.
