Héloise Mowbray was born on a freezing February morning to an exhausted, starving Muggle couple in a collapsing French seaside cottage. Their five-year-old son watched as his mother screamed in agony with terrified eyes, and slept for three days afterwards, her frail body struggling to not fall apart. Héloise was unplanned, a complete accident, as the couple had vowed to never have another child after the debt their first child had dragged them into. They'd barely been able to feed Timothy, and now they had another mouth to feed. That's all they ever saw their daughter as. Another mouth to feed.
Maurelle knows why her children are magic - she was a Squib, born into one of the largest magical families in the world, and a great disappointment to her magical parents. She wasn't treated any where near as well as her siblings (who had all gained the magical powers), and once she'd graduated, was immediately thrown out. Maurelle has been starving her whole life. A glimmer of hope appeared when she married Carleton, but he was barely surviving on his tiny wage as a backstreet blacksmith, and the birth of their first child dragged every single penny from them.
Growing up in a crappy little cottage in the freezing cold was hell, but it was only when Héloise was five when Timothy took a stand. Some people questioned the nine-year-old boy strolling down the street with his little sister in hand, but they were mostly conspicuous. Sneaking onto a ship unnoticed was quite easy, since they were both small and underfed, and they found themselves in England.
Timothy worked hard to keep him and his sister alive - he helped at the marketplaces, earning coins here and there which he later bought food and clothes, but he also pick pocketed. And he was damn good at it - he's only improved, and never been caught. He discovered an abandoned cottage, not dissimilar to his old home, but in much better condition, and immediately moved him and his sister into it. It was warm and cosy, since all the windows and doors were intact, and for once, they were happy.
Timothy then took the opportunity to completely rid themselves of their pasts, and he changed his name to Robyn, then asked Héloise what name she'd like. Having heard the name Ivetta at the market and immediately fallen in love with it, she chose Ivetta. The pair also started telling people they were Purebloods, so they could fit in without being prejudiced.
Robyn knew that Ivetta was magic, and Robyn recieved his letter to Hogwarts on his eleventh birthday. He didn't dare abandon his sister though, and wrote back, begging the Headmistress to let him bring his sister along, to which she allowed. Ivetta stayed in the Head Girl's dormitory until she hit eleven years old and was sorted into Ravenclaw.
Unfortunately, the headmistress has now demanded that Timothy and Ivetta live in a Muggle orphanage, simply to "keep them safe", according to her. Ivetta hates it at the orphanage - she's treated like trash and locked in her room most of the day and much prefers living at Hogwarts.