Beautifully-written and imagined, with great lines that make so clear why Petunia hates magic and why she doesn't, can't, and doesn't want to understand:
Petunia was left with the dank taste of reality in her throat, of waitressing, of bills, of not being able to make ends meet.
It's a world of no consequences if broken plates can be fixed so easily.
Here's perhaps the essence of Petunia's hostility:
Petunia was only four, but already she knew that she was second best to Lily. It wouldn't have been so bad if she didn't agree.