Dido was an accidental child. Her mother Claudette, a tarot reader from Soho, London was struggling to pay bills and make ends meet - a common fate for many Londoners who hadn't been to university and gotten a degree, and given the ridiculous price of housing (but that's neither here nor there). Anyway, Claudette eventually got a client who was offering a marginally higher price for Claudette's services than usual. He was tall, dark, and frighteningly handsome, hailing from Tunisia. Now, Claudette herself had no magical powers, she made her money by playing to clues, sleight of hand and very good empathy. She also knew a few tricks from her own mother, who was a witch herself, and possessed the sight. Yes, Claudette was a squib, but she had the best teacher to fake her way into a decent living.
And so Claudette went on with the shtick, she burnt incense and recited some of her mother's native Creole 'spells', in general, wowing the customer. He was spellbound by this mystical woman and asked her for dinner. Claudette agreed, she was young still, and this man could potentially have changed her life, he had money and status. The two had a good time, and eventually, Dido was concieved. But with Dido's conception, the mysterious stranger was lost. He was gone in the morning, before Claudette could even say farewell. It was a harsh and cold awakening, but eventually the Tunisian man became a distant and foggy memory, to the point that Claudette couldn't even remember his name.
None of it mattered, though. Dido brought more light into the life of Claudette than anyone did. She was always a happy baby, and a creative toddler. As far as Claudette knew, Dido was a normal nonmagical child. The first sign of magic was displayed rather late, around the age of five. It was unconventional, too. Dido was playing with her mother, and all of a sudden her eyes went marbled and pearly, and she spoke in three voices, predicting the next four day's weather. It was a very mundane thing to predict, but she was completely correct. Claudette knew she must have been a witch at that point, as the same thing happened to her mother when she was predicting something. She knew then that Dido had the gift of magic and also the sight.
Affirmation came not long after, on the eleventh birthday of Dido. The Hogwarts letter came, and Claudette took her to Diagon Alley to get the full regalia. She was hopeful, that young Dido would have a better chance in life than she, and she always made sure Dido remembered this. She is currently in her third year at hogwarts.