Sybill is the great-great granddaughter of a genuine Seer, Cassandra Trelawney. Cassandra’s gift has been much diluted over ensuing generations, although Sybill has inherited more than she knows. Half-believing in her own fibs about her talent (for she is at least ninety per cent fraud), Sybill has cultivated a dramatic manner and enjoys impressing her more gullible students with predictions of doom and disaster. She is gifted in the fortune teller’s tricks; she accurately reads Neville’s nervousness and suggestibility in his first class, and tells him he is about to break a cup, which he does. On other occasions, gullible students do her work for her. Professor Trelawney tells Lavender Brown that something she is dreading will happen to her on the sixteenth of October; when Lavender receives news on that day that her pet rabbit has died, she connects it instantly with the prediction. All of Hermione’s logic and good sense (Lavender was not dreading the death of the rabbit, which was very young; the rabbit did not die on the sixteenth, but the previous day) are lost: Lavender wants to believe her unhappiness was foretold. By the law of averages, Professor Trelawney’s rapid fire predictions sometimes hit the mark, but most of the time she is full of hot air and self-importance.
Nevertheless, Sybill does experience very rare flashes of genuine clairvoyance, which she can never remember afterwards. She secured her post at Hogwarts because she revealed, during her interview with Dumbledore, that she was the unconscious possessor of important knowledge. Dumbledore gave her sanctuary at the school, partly to protect her, partly in the hope that more genuine predictions would be forthcoming (he had to wait many years for the next).
Conscious of her low status on the staff, who are almost all more talented than she is, Sybill spends most of her time apart from her colleagues, up in her stuffy and overcrowded tower office. Unsurprisingly, perhaps, she has developed an over-reliance on alcohol.
Professors Trelawney and McGonagall are polar opposites; the one something of a charlatan, manipulative and grandiose, the other fiercely intelligent, stern and upright. I knew, however, that when the consummate outsider and non-Hogwartian Dolores Umbridge attempted to oust Sybill from the school, Minerva McGonagall, who has been critical of Trelawney on many occasions, would show the true kindness of her character and rally to her defence. There is a pathos about Professor Trelawney, infuriating though I would find her in real life, and I think that Minerva sensed her underlying feeling of inadequacy.
I created detailed histories for many of the Hogwarts staff (such as Albus Dumbledore, Minerva McGonagall and Rubeus Hagrid), some of which were used in the books, and some of which were not. It is in some ways fitting that I only ever had a vague idea of what had happened to the Divination teacher before she washed up at Hogwarts. I imagine that Sybill’s pre-Hogwarts existence consisted of drifting through the wizarding world, trying to trade on her ancestry to secure employment, but scorning any that did not offer what she feels is the status due to a Seer.
I love Cornish surnames, and had never used one until the third book in the series, so that is how Professor Trelawney got her family name. I did not want to call her anything comical, or which suggested chicanery, but something impressive and attractive. ‘Trelawney’ is a very old name, suggestive of Sybill’s over-reliance on her ancestry when seeking to impress. There is a beautiful old Cornish song featuring the name (The Song of the Western Men). Sybill’s first name is a homonym of ‘Sibyl’, which was a female clairvoyant in ancient times. My American editor wanted me to use ‘Sibyl’, but I preferred my version, because while it keeps the reference to the august clairvoyants of old, it is really no more than a variant the unfashionable female name ‘Sybil’. Professor Trelawney, I felt, did not really qualify as a ‘Sibyl’.