Kate Middleton and her husband, Prince William, are expected to uphold the annual tradition of releasing a new photograph marking their children's birthdays. Their youngest, Prince Louis, will turn six on April 23.

A source revealed to a British news outlet that Kate Middleton and Prince William are planning to release a photo to celebrate Prince Louis’ sixth birthday next month.

Kate Middleton, 42, has not been seen in public since undergoing abdominal surgery in January, fuelling speculation about her health.

An announcement on January 17 by the Kensington Palace office said that the Princess of Wales was admitted to The London Clinic on January 16 for a "planned abdominal surgery".

Also, Princess of Wales Kate Catherine is likely to address her health concerns at a public event, the UK newspaper The Times reported.

"I can see a world in which the princess might discuss her recovery out on engagements. If she was going to do it, that's how she would do it. I would expect that to be her instinct and it will be her call. They're not going to be rushed," the source was quoted as saying by the daily newspaper.

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