Ayla Kerr is a six-year-old girl from the UK who suffers from celiac disease, a chronic autoimmune disease that requires patients to follow a strict gluten-free diet. Last December, her mother Kirsty wrote a letter to Kate Middleton and now they got an answer.

The mother sent the letter as part of the Shaping Up campaign, which focuses on children's mental health, and decided to do so because her daughter felt isolated from her schoolmates, Hello magazine writes.

"I've never seen anyone really talk about how the disease affects children's development and their mental health, it's something that's completely out of their control.

I started by writing that it is a very strange feeling when I write such an official letter – from one mother to another, because she also has three children. Who knows what they are going through because they are also different, but for a completely different reason," she explained, and eight months later they received an answer from Kate Middleton's office.

In the letter, the princess wrote that she was sorry for the problems the little girl was facing and sent her best wishes to her mother and the whole family.

The mother explained that the letter from the Princess of Wales made the sick girl very happy.

“She was absolutely thrilled and excited. She thinks Kate is the most glamorous woman in the world," said Kirsty.

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