Hello hello! I'm Kaylie, and I really need to learn my characters' hogwarts years.
Let's see... I have Ron Weasley (1991 - 1998) so he would have overlapped with Celia and been in the same house. He wanted onto the quidditch team but never made it because without Felix Felicis he never actually believed he was good enough. He's also youngest of six! Or was, until Ginny came along and made him second-youngest of seven. It still counts, and he is also one of fiery temper so they'd either get along or hate each other.
Then I have Bethanie Dunstan (1988 - 1995) so she'd have overlapped by like a year. She was a prefect during that year, though, so she'd have been welcoming. They're probably a bit far apart to have much connection though.