Valaire wasn't always raised by Snape. In the year of 1982 her parents Luna Desando a pureblood and Luke Alverz a Mudblood met . The only problem was that Luna was a year 3 and Luke was a year 5. They dated anyway a few years later. They had Valaire but couldn't keep her since it was against Hogwarts rules for students to have children so the two went to Snape to take in thier daughter.