Neither of them wanted to bring up the events of their son's last birthday. At some point they were going to have to have an uncomfortable conversation. Hermione hoped that she could delay that moment for as long as possible. It upset her to know that she'd ruined his eleventh birthday. Few birthdays were as exciting and important to a wizard, and she'd almost killed his father on his. Thanks to their dysfunction, it wasn't as if he had much in the way of family. If Hermione had succeeded in her hasty plan, she wasn't sure what would've happened to Oliver.