- "When are going to learn that I am not my brother?! I am Alex, not Nicolas. Nico is dead! If you are hoping that you will see him in me then I suggest you leave right now."
- —Alex reiterating to Nadia that he is not his brother
During school, Alex was very close with his brother and, by extension, his girlfriend, Nadia. Alex was frequently picked on by a group of students until his brother put a stop to it, albeit at the cost of expulsion. During the European Junior Quidditch Championship, Alex attended the Quidditch match between Carpathia and Durmstrang; his brother being Carpathia's star Seeker. There, he watched in horror as his brother was struck by lightning and fell to his death. His passing affected Alex deeply, and the grief brought him closer to Nadia, the two later beginning a relationship shortly after the funeral. Overtime, Alex and Mateo grew closer as well, becoming best friends and even becoming magically bonded brothers.
After his graduation from Cornivus Academy, Alex became an Arithmancer while growing herbs on his downtime, selling them to the Hungarian Ministry for use in healing. He married Nadia in 1996 and with her, had three children; Nicolas Fábián Mihalios (b. 1997) and twins Mateo Alexandru and Franciska Nadia Mihalios (b. 1999).