Deep Question- do you pour the milk in first, or do you pour the cereal in first?

This has been ugging me for a while. Plus I met this bratty girl at a sleepover and in the morning, when I was getting some cereal, I poured the cereal in first and she was like, "You're doing it WRONG! Puh-lease!" and it was so rude. Anyway, I'm just wondering!