Alex was born into a fairly well off family, his father (Garrick Reid) being a portioner who has gained notoriety in recent years. Meanwhile, Alex's mother (Renee Bennet) has long been absent from his life; when he was six, she simply vanished without a trace. Alex himself, is not sure what happened to her, due to his father's refusal to speak of her sudden disappearance, and he has been extremely frustrated by the fact that no one is telling him anything.
Even before his mother was gone, Alex had a bit of a strained relationship with his father. Garrick spent most of his time traveling and searching for new potion ingredients. When he is home, he spends most of his time making sure that Alex basically lives in a bubble. Whether it's because he's an only child, or due to his chronic health issues (primarily a congenital heart condition), Alex isn't sure, but he finds it suffocating. One of the few ways he can enjoy himself within the bounds his father sets is by spending time in the family library. While some of the age-old titles the elder Reid keeps on his shelf are rather dull, they did help foster an enjoyment of reading and learning in Alex.
When a letter from Hogwarts arrived at his doorstep, Alex was overjoyed. Not just at the concept of going to such a prestigious school, but also the idea of the freedom that came with it. 

Personality:
Because he rarely socializes with anyone outside of his family, Alex tends to become flustered in social situations and can come off as being quiet or, in some unfortunate cases, full of himself. He often doesn't feel like he can be himself around others and tries to keep to himself because of it. This problem tends to persist even when he gets to know others. He can seem annoyed with those around him at time, but he does genuinely care about his friends and will take care of them when he can. While he's not as comfortable with his other skill levels, Alex is very confident in his own intelligence, and sometimes even overestimates it. However, he is very physically frail, and very self conscious about this.