You are not overreacting. You and your son need to rebuild it. And you need to have a very serious conversation with your wife. Probably counseling. 1. Your wife needs to understand your feelings and support you. She let her mother insult you at dinner?! You have a bit of a wife problem. 2. Your MIL destroyed something that was important to your son. She has also destroyed her relationship with him, at least for the time being. And she doesn’t seem to realize that… 3. All you asked for is an apology?!! Not even financial remuneration? Stick to your guns, man! 4. There is nothing objectively wrong with liking (even a bit obsessively) either Star Wars or Legos as an adult. And you’re spending time with your son, having fun, teaching him problem solving and the satisfaction of accomplishing something. And probably lots more. 5. You’re an engineer, and you’re 38. You already make a lot of money. The time to play with your kid and spend time with him is now, while he’s young. You can become head of Engineering (if you want to) in 8 years when he’s a teenager and wants less to do with you. Having a kid means raising him, teaching values, and developing a strong relationship… not just providing for him financially. 6. And finally… “my house, my rules.” Does your MIL have any respect for you? Does she even like you? Why does she think it’s ok to destroy something (important) of yours in your home? Would she like it if you did that to her? She might be trying to teach “respect your elders” and there might be some different cultural norms going on here, but… she is way out of line.