When I first received my Hogwarts letter, I was more than surprised. Sure, it would explain, why I was so weird compared to my classmates, but I always thought it was because my views and interests differed from theirs. Thank Merlin for that though.
After overcoming the initial shock, my mother proceeded to investigate our family's history, worried that this whole thing was a scam. Later on though, she would tell me about, how her mother would sometimes tell her that we were a family of wizards. My mother though hadn't been able to believe her back then, since she had seen my grandmother become delusional and forgetful as Alzheimer claimed her brain.
Upon the realization that my grandmother might have been telling the truth, things sped up considerably, because not even a year later we were ready to move to England so that I could attend Hogwarts, while my mother would try and discover the extent of her own magical abilities.