Is this grammatically correct? What does it mean? Any possible rephrasing? My sister told me about what happened

Yes, the sentence "My sister told me about what happened" is grammatically correct. It means that your sister shared information or recounted an event that occurred. Possible rephrasing includes: - "My sister informed me about the incident." - "My sister shared with me what took place." - "My sister explained to me what happened." - "My sister told me what occurred." All of these rephrasings convey a similar meaning, implying that your sister communicated details about a particular event.