The Lovell's and Montcroix's were two great wizarding families who had been feuding for many years - centuries, even. Some say it originated as far back as The Hundred Year war, whilst others pinpoint it more around the time of Napoleon. Regardless, the two families had been feuding, declaring each other as their bitter enemies for whatever reason. The families were deemed great both magically and to the muggles; to the former, members of each family had been innovative in shaping magic for the respective countries of England and France and, for the muggles, each family was known to be high up in society. Theories speculate that the whole feud had started when one family wanted the other's interest but others prefer not to delve deep into it and enjoy the drama.
An interesting blip, an abnormality in their history between the two, occurred late in the twentieth century. The ruling patriarchs had died in each family, leaving their far less involved wives to head the families until their demise. The wives, wanting some peace amongst the historic conflict, had set up their youngest adults; for the Lovells it was a man in the main branch, Alexander, and for the Montcroix's, his seeming counterpart, a woman named Adele. The two were set up, forced into an arranged marriage and encouraged to procreate. It was lucky for the matriarchs that neither had any major objections - both were content and, perhaps naively, convinced themselves they'd live a good and drama-free life.
Astair wasn't the first result of the marriage, no, there were four brothers and five sisters he had to compete with first. In fact, Astair was the last thing to come from it and, arguably, the last happy thing. After Astair was born, the two matriarchs who had wholly supported the relationship and it's offspring had passed, leaving the now twelve-strong Lovell-Montcroix family isolated. Everyone else in the two families had despised the relationship, stating that the other family's member amongst their own was destructive and contaminated what otherwise was pure and perfect blood. The still young couple decided to ignore it, moving to a remote wizarding village in the Welsh countryside to avoid it all.
Growing up was a fond memory for Astair; he had a great childhood. His parents allowed him and his siblings to not only dabble in the magical society but also the muggle one. Astair got the best of both worlds - as his older siblings grew up they showed him the magic of Hogwarts and the technology of the muggles. He loved it and had made sure to aspire to be the same. His first magical experience was the result of his older siblings too; they were showing him basic spells, amusing the six-year-old Astair greatly, and he tried to replicate them. In the past all attempts had failed but, by some sheer luck, he managed to recreate it. Unfortunately the recreation was a flame that burned a sofa but it was the experience that counted, at least in his parents' eyes. From that moment on, Astair grew up with a more magical based life but was still permitted the muggle luxuries his siblings once had.
Like his siblings, Astair got his Hogwarts acceptance letter at the age of eleven and went off, being sorted into Gryffindor - the only one of his nine other siblings, much to the pride of his father, a fellow Gryffindor. A lot happened during his years at Hogwarts, mostly all for the worse. It was during his time as a student that the Lovell's and Montcroix's feuding had reached a new height - there were many raids and attacks on each other and unfortunately his family was in the very harsh position on having to choose a side. Most, viewing themselves as Lovell's more due to the connection of a similar culture, chose the aforementioned, leaving the Montcroix's outraged.
From that rage a lot of Astair's immediate family perished; he lost his father, three brothers and four sisters. The once twelve-strong Lovell-Montcroix branch had only four members left; Astair, his mother, an older brother and an older sister. The family moved again from the Welsh countryside to a magical community in Oxfordshire, one where the Lovell's had a large presence and the family was guaranteed to be protected.
Despite the drama happening outside of Hogwarts, Astair graduated with impressive results and immediately trained to become an Auror. While it took a while, he rose to the challenge and found that he excelled at it. There were times where he had to persecute members of either family which took a toll of him because, at the end of the day, they were his family, but he persevered and made a name for himself.
It was in the following years that he met a muggle woman, one he fell in love with quickly. She reciprocated his love and within a year they were married. She always knew about his life, his legacy and his job and knew that any child with him could be involved in that life, and that his job was demanding. At first, she was fine with it and even gave him a daughter - Charlotte.
Things got harder when Charlotte was three - her mother had decided that the life of a wife of an Auror wasn't for her and that she'd much rather prefer to be with a muggle man. So she left, just like that. She left them without a trace and forced Astair to pick up the pieces and try to be the mother Charlotte needed.
Eight years on, he thinks he's done alright - Charlotte's a fine young woman in the making, if you ask him, and he's recently been promoted to the Head of the Department of Magical Law Enforcement. If you ask him, he's in the best place of his life.