I wiggled out the large book from the bottom shelf between the Oxford English Dictionary and Roget’s Thesaurus. The book was so heavy that I had to kneel on the carpet and rest it on my knees. My fingers scurried over the pages to the index section at the back of the huge tome. The pages were thin and slippery but smelled comforting. For me, books had a perfume of their own. Warm, musty, exciting.

I’m a bookworm and a booksniffer – a bookdog.

I had a good, long sniff. This encyclopaedia was about ten years old, so quite new, but it smelled good and booky, and I already knew it was full of modern, up-to-date science I could trust.

In the index I found the word I was looking for: allergy. I trailed my finger down the allergy sublist looking for ‘light’, but it wasn’t there. I carried on down and spotted the word ‘sun’. Sun allergy, pages 222–225. I flipped to page 222 and immersed myself in information about ‘Solar Urticaria’ (SU). SU was a rare condition where exposure to ultraviolet radiation or sometimes even visible light brought on a case of hives that could appear in both covered and uncovered areas of the skin. That sounded like the condition Clarabelle and I had! I lingered over the word ‘rare’ for a few moments – disturbed by the idea that rare meant very few people in the whole world could have the condition. The words too much of a coincidence skittered across my brain, but I read on, desperate to know SU’s symptoms and effects.

Areas affected are bare skin not usually covered by clothing; however, it can also occur in areas protected by clothing. Skin regularly subjected to sunlight may only be slightly affected, if at all. Those with severe cases will also have reactions to light bulbs that produce a UV wavelength. Sparsely covered parts of the body can also be affected by this form of light.

In some cases, life with SU can present a plethora of difficulties. Some patients experience persistent itching and pain resulting from the rash (a result of exposure to UV radiation). If large areas of the body are affected, the loss of fluid into the skin may cause headache, dizziness and vomiting. In very rare cases, people may experience a stroke or heart attack due to swelling in the body. Other side effects include bronchospasm and glucose variability problems. If a vast area of the body abruptly comes into contact with the sun’s rays, the individual may have an anaphylactic reaction. However, away from light, the rash will usually diminish within several hours. In severe and rare cases, the rash can take one to two days to fade.