Back story, my mum almost died after heart surgery last year. This year, for her birthday I'm planning a family meal. I have just invited my in-laws and they are happy to come, both sets of in-laws get along. However, my MIL has just messaged to ask me if I'd invited my husbands brother. We don't really have much to do with him, although are civil and on speaking terms. My parents know him but haven't spoken to him for years, probably about 14 years ago when we got married. He's not the easiest person to get on with and I don't really want him there, it is after all my mums birthday and he wasn't mentioned as part of the plan. My MIL is lovely and I get on really well with her but she will most definitely get her ass in her hands if I say I'm not inviting him. AIBU not inviting him? What should I say?