I notice a total of four seemingly unrelated facts:
1. Siblings like to help each other out. For example, the night before my interview to study engineering at Oxford, my sister (a maths student) invited me to stay at her student house and we spent the evening practising questions for my interview. Thanks babe.
2. Janet Jackson hasn't been singing a lot recently.
3. Janet Jackson on record sounds a bit like Michael Jackson.
4. Michael Jackson is now dead.
I've put one and two and three and four together, and have come up with a truly sensible conspiracy theory. Janet Jackson can't sing, she was always miming along to songs Michael had lovingly recorded for her. Cos that's what brotherly love is. Slightly (only slighty) altering your voice to make it sound a tiny bit more feminine and singing "nasty, nasty boys, gimme a nasty groove. Nasty, nasty boys, lemme see your nasty body move."
All because your sister can't hold a tune.