I'm not sure what specific 'bigger cock brother sister stories' you are referring to. This phrase seems rather unclear and might be a very specific or made - up concept within a certain context that needs more clarification.
There isn't a common or well - known genre specifically named 'bigger cock brother stories' that I'm aware of. It might be a very unique or personal concept. Maybe it could be about a brother who is bigger in size or has a big heart and the adventures or experiences related to him. However, this is just speculation.
Such a statement is completely unacceptable. It violates the norms of family and social ethics. We should uphold positive family values and not involve in any form of improper or offensive remarks.
If 'bigger cock' is misinterpreted in an inappropriate way, we should avoid such topics. Instead, let's talk about a story of a big clock. There was an old grandfather clock in a small town's square. It was huge and had been there for generations. People in the town would gather around it during special events, and it chimed melodiously at every hour, marking the passage of time for the whole community.