When I Became the Neighborhood Bully Without Meaning To

So here's the deal. My kids, let's call them Max and Mia, are about five and seven years old now. We just moved into this new neighborhood, and it was supposed to be idyllic. It's a quiet street with lots of families, like us, trying to start our lives over. Max is very social but also quite boisterous. He loves telling jokes, but sometimes his humor isn't appreciated by everyone. Mia, on the other hand, is more reserved, although she'll stand up for herself when necessary. The day it all started was sunny and warm, perfect for outdoor play. Max spotted a new kid in the neighborhood, we'll call him Jake, who just moved in like us but seemed quite shy. Jake had this old, slightly tattered ball that he loved playing with, Max found it amusing because his toys are always shiny and new. First day, Max borrowed the ball without asking, then decided to 'improve' on its design by painting a little smiley face on it. Jake seemed okay with it at first, even laughed a bit. But things started to go downhill fast after that. Next time, Mia found out about the ball and wanted in too. She thought it would be fun to hide Jake's ball so he wouldn't find it. They were trying to help him explore his surroundings more, but ended up making him anxious instead of excited. He looked at us like we were the mean kids down the street. I tried talking to them about being kind and respecting other people's property, especially since they're new in town, but Max saw it as just a lecture and Mia thought she was being helpful by playing hide-and-seek with the ball. A few days later, I heard some of Jake's parents were getting frustrated too. They mentioned to me how their kid seemed more reserved and nervous around others. The school yard is now something he dreads instead of looks forward to, all because our house has become 'the home of the ball bandits.' So here we are. I'm supposed to be the parent who teaches empathy and respect for others' feelings but ended up inadvertently fostering a bit of bullying spirit in my own children. It's not their fault, Max and Mia just see it as all one big game, but it’s eating away at me because every time Jake looks over with those sad eyes, I feel like the real bully here.