I have not heard her sing, but I take your word on it, maybe booing her was not nice, but when you are an entertainer, you have to take the bad along with the good, I mean how else is the audience supposed to react, clap for her bad performance, then she will never know that she needs to up her performance.

Sorry but it is all part of the job, maybe she is cashing in on her sister's name and needs to look for another career.